Updated on 07.29.14

# How Much Is Your Time Worth? Thoughts on Speeding

Lately, I’ve been thinking a lot about the costs and benefits of speeding. Is pushing the pedal a bit actually worth it? Or are you better off staying inside the speed limit?

In order to start cranking the numbers on this, I had to use a few assumptions. Let’s walk through them.

First, I figured that you have 1/4% chance of receiving a speeding ticket for each mile you’re over the speed limit for an hour. So, if you drive 68 in a 65 zone for an hour, you have only a 3/4% chance of receiving a ticket. On the other hand, if you drive 82 in a 65 zone for three hours, you have a 12 3/4% chance of receiving a speeding ticket.

Second, I figured the cost of a speeding ticket is \$200 and has a ten minute time cost. The ticket itself will cost you less than that, but the raise in your insurance rates from that ticket will eat the rest.

Third, I figured you lose 1% fuel efficiency for every mile per hour over 65. I’m using government estimates for this figure.

Fourth, I’m using a figure of \$2.50 a gallon for gas, and I’ll use a car that get 25 miles per gallon for the calculation.

Got that? Let’s get cracking.

Is it more efficient to drive 80 miles per hour or 65 miles per hour on the interstate? Let’s say you’re making a 200 trip on the interstate.

If you go 65, you have zero chance of receiving the speeding ticket. You’ll consume 8 gallons of gas and arrive in three hours and five minutes, costing you \$20.

If you go 80, you have an 11.25% chance of receiving a speeding ticket. If all goes perfectly, you’ll consume 9.4 gallons of gas and arrive in two hours and thirty minutes. However, if you receive a ticket, you’ll arrive in two hours and forty minutes – that’ll happen 11.25% of the time. So, combining the odds of the two, an average trip driving 80 will allow you to arrive in two hours and thirty one minutes (saving thirty four minutes) and cost you \$46.03.

So, driving faster saves you thirty four minutes but costs you \$26.03 – an hourly rate of \$45.11 for driving slower.

What about going 70? You have a 3.75% chance of receiving a speeding ticket. If all goes perfectly, you’ll consume 8.4 gallons of gas and arrive in two hours and fifty one minutes. However, 3.75% of the time, you’ll receive a ticket and arrive in three hours and one minute and drop \$200 on that ticket. So, combining the odds of the two, an average trip driving 70 will allow you to arrive in two hours and fifty two minutes (saving thirteen minutes) and costing you \$28.55 (costing an average of \$8.55 more). Your hourly earnings from driving 65 instead of 70 is \$38.91.

What about going 66? Only a completely malicious cop bent on getting their quota would give you a ticket then – you have a 0.75% chance of getting a ticket over three hours. If all goes perfectly, you’ll consume 8.1 gallons of gas and arrive in three hours and two minutes. However, you have a 0.75% chance of getting a ticket, and if you do, you’ll arrive three hours and twelve minutes and get a \$200 ticket. Combining the odds, on an average trip going 66, you’ll arrive at three hours and a bit over two minutes (saving a bit under three minutes) and spending \$21.70. Your hourly earnings from driving 65 instead of 66 is \$36.50.

Here’s the data up through 120 miles per hour. The data in the “TRIP COST” column is the total cost (gas plus odds of a speeding ticket) of an average 200 mile trip on the interstate at that speed in a 25 miles per gallon car. The “SPEED COST” indicates the total cost you incur by going that speed instead of going 65. The “MINS SAVED” column tells you how many minutes you save by going that speed instead of 65. The “HOURLY” column indicates the hourly wage you earn by simply going 65 instead of speeding. So, for example, if you go 120 miles per hour, your trip costs, on average, \$126.94, which is \$106.94 more than you’d spend if you drove the speed limit. Driving this fast saves you 84.6 minutes on average, though, so if you drove the speed limit instead of going this fast, you’d earn an hourly rate of \$75.83 for your time.

Conclusions
First of all, each mile per hour you speed is more costly than the one before it. Going from 70 to 71 is more costly than going from 69 to 70. That’s fairly straightforward, though.

Second, if you look at it in terms of an hourly wage, speeding can be pretty costly. Remember, we’re talking about after-tax dollars here, not the raw amount you bring home. Thus, a \$36.50 hourly rate for the two minutes and forty eight seconds you spend driving 65 instead of 66 is more like \$50 or \$55 an hour in pre-tax money. The chances of a speeding ticket are more costly than you might think.

Third, this doesn’t include a “wear and tear” factor. Continually speeding puts additional wear and tear on your car – an amount that’s hard to quantify. With an enormous pool of real-world data, one could come up with a factor for this, but it would simply serve to make the cost of going faster even higher.

Fourth, this is all about probability. You’ll hear from people who claim to always drive eighty and never get a ticket. Others may get a ticket going 37 in a 35 (the ticket said 42, but I was going substantially slower – an officer was pretty obviously trying to get a quota filled). One lucky person is a great anomaly, but it doesn’t change the simple fact that the faster you go, the more likely you are to get a ticket.

Finally, some people with a high value on their time can justify speeding. If you are hurrying to a place so you can start billing \$100 an hour, there might be a great justification in speeding. However, the more you push it, the less you actually gain, because the hourly cost for each mile per hour goes up.

However, on most road trips, you’re better off setting the cruise control at the speed limit and just cruising along. Getting to Aunt Melba’s ten minutes earlier isn’t worth the potential cost for most people.

The comments on this one should be fun. All I suggest is that you shouldn’t get bogged down in picking apart the assumptions, because even radically changing them still results in the same conclusions. I tinkered with and researched the assumptions extensively for this post and found that even if you modify the assumptions radically, the conclusions still hold.

1. Nathan says:

I think your odds of getting a ticket are way off, if only because they should be mapped at prevailing speeds and not speed limits. Also, if there is a 12 percent chance of getting a ticket at 80 mph (I rounded) then there should be 12 cars pulled over for every 100 driving 80 or more on the road.

I regularly drive to NH — a six hour trip — at the prevailing speeds of between 70 and 85 MPH and have never seen 5 people pulled over in a trip.

2. Aristotle says:

Safety is another consideration that could be stated in dollar terms. The probability of dying (rather than merely being injured) in an accident increases with speed. So the driver both increases his ability to bill \$100/hour by speeding (thereby getting to the engagement on time) and increases the likelihood he’ll never bill anything again.

3. Jeff Jewell says:

Sorry, I have to pick apart one aspect of your assessment… I see two problems with the 1/4% per mile per hour rule.

My first problem is that I cannot support the notion that this is a linear function… I would suggest that the risk percentage grows exponentially as speed rises.

My second problem is your inherent assumption that there is no chance you will ever receive a ticket traveling at the speed limit. Between equipment variability and the quotas you mention, I suggest it’s essentially equally possible to get a ticket for going 65 as it is for going 66.

Interesting assessment, though, thanks!

JJ

4. MichelleO says:

I second Aristotle’s comment regarding safety. It’s not uncommon for people who are speeding, especially substantially, to frequently change lanes and tailgate others. This also leads to higher frequency of accidents. You’re not just playing with your own life, but those who happen to be in the vehicle or on the road with you. Speed limits were created for safety reasons in addition to fuel economy.

Also, the stress that you create for yourself by speeding, i.e. rush, rush, rush, isn’t at all healthy for you.

5. Tyler says:

I wrote an article on hypermiling last week and this post does a great job of illustrating the costs of one of my points – just slow a down!

I admit that I used to drive like an @\$\$*%&# until I realized that I was just wasting money, stressing myself out, and putting myself and others in harms way, and for no good reason. Just the lowered stress from chilling out and slowing down has made such a difference in my life. Going on a nice little trip should not elevate your blood pressure!

6. tomasz says:

Perhaps the problem is not knowing how to drive efficiently. Not everyone that speeds, tail gates or weaves through lanes, even if they do, not all of them do it unsafely.

Even if you don’t speed, you are at risk of getting hit by someone else that may be speeding.

In the end, we risk death every moment, no matter how safe we are, so really what is the benefit of being safe all the time when one careless act by someone else could send you away?

7. carrythebanner says:

Also really surprised that you didn’t mention safety, even in passing (no pun intended), especially given how much you talk about being a parent. If the kids in the car with you, it just multiplies the risks you take.

(I’m talking here mostly about going significantly over the limit; I realize there’s not a large difference in safety going 67 vs. going 65.)

8. I do not know how police works in Us, but here they use autovelox and so the chance of receiving a ticket it’s the same if you drive at 70 or 100 over a 65 limit: you receive that if the police is there.

9. tambo says:

Living in rural Iowa, it seems like pretty much everyone ‘speeds’, the question is how much. I set the car’s cruise control at 2-3mph over the limit (and have often driven right past police cars without so much as a blink) but I am constantly passed by people going much, much faster. I almost never pass anyone other than tractors, in fact at 58mph on a 55mph highway, I’m the slowpoke. Folks here routinely drive 62-65mph, even on gravel roads. There’s no way I’d have tried that when we lived in Des Moines.

10. thefamilynomics says:

Interesting way to look at things. Safety is always the key.

11. marta says:

All this talk about the value of your time and hourly rates can get tiresome after a while. Rather than speeding tickets I would worry more about safety and the consequences of reckless driving.

I’d rather lose one minute of my life than lose my life in one minute, thanks. Even if that minute is worth 5 bucks (giving a hourly rate of, wow, 300 bucks).

12. Fr33d0m says:

I think MichelleO misstates the stress component but thats a bit subjective and so a footnote in this post. I don’t think speeding leads to a “rush, rush, rush” attitude as much as that attitude leads to speeding. The stress felt by speeders is likely to manifest itself as tailgating, unsafe passing, and roadside rage.

That said, I can’t believe you missed the gorilla in the room here–safety. The amount of rubber–the footprint–that contacts the road at 55 MPH is nearly an inch and it gets smaller for each MPH above 55 that you travel making each increase in speed exponentially riskier. There are plenty of statistics out there to show how the odds of an accident increase as speed increases. Accident repair, insurance increases, loss of work time–even the possibility that you could be charged for vehicular manslaughter are potential outcomes short of the loss of your life.

13. Kathryn says:

I’m not sure i agree with all your conclusions as i drive the freeways in Southern California quite a lot. Unless you are going significantly above the speed limit (15+ MPH & more) the chance of getting a ticket is very, very low.

That said, i got 2 very expensive tickets in 1991. I was in college at the time. The speed limit was 55 MPH. The first was late at night. Honestly, my speedometer was broken, but there were no other cars around & i couldn’t gauge my speed very well, but i probably would have been going that speed anyway (75). \$275. (Remember 1991.)

After that i kept myself in the slow lane & worked very hard at sticking to the 55, but one day trying to get over 3 lanes where 2 freeways came together to make my exit no one would let me in & i went around them. Right in front of a cop. I was so angry because i had honestly been trying to stick to 55 for months. Another \$250. I decided that was not worth it & determined i would stick to the speed limit from there out. And i got the speedometer fixed.

Driving slower opened my eyes to a lot of things. In general i slowed down my ATTITUDE. I saw more as i was traveling. I felt i was driving safer. I left a few minutes earlier than before, or if i was running late i reminded myself that being 5 minutes late could never justify an expensive speeding ticket. I irritated a lot of other drivers but i did stay in the slow lane. And i saw that a lot of folks do justify their speeding. If nothing else they apparently think they are more important than the rest of us as they weave in & out to get 2 cars ahead.

I travel about 250 miles a week now. The speed limit is 65. I carpool with my husband. I do drive a little over the speed limit, probably averaging 72 MPH. I’ve not had a ticket since 1991.

What is amazing is the behaviors i see on the freeway. There are a lot of people who tailgate. Since i’m in the carpool lane there isn’t anywhere i can go, & i can’t go faster than the folks in front of me. I do leave a lot of room between myself & the car in front, but if we are going the same speed, that doesn’t matter except in terms of safety.

I have folks drive less than 2 car lengths off my bumper at 72 MPH. I HATE that! And if they have a chance to go around me (me leaving maybe 10 car lengths between myself & the one in front) they tail gate that one in front of me. What have they gained by this dangerous behavior? Probably not even a minute in time. When is it worth this?

These days i have the idea that i am NOT more important than everyone else on the road. I try to drive courteously. But if you are tail gating me i WILL slow down.

14. Marsha says:

You wrote “I figured the cost of a speeding ticket is \$200 and has a ten minute time cost.” Alternatively, if you choose not to pay the ticket, you’re going to have to spend several hours either going to court or taking one of those lame defensive driving courses.

15. cynthia says:

Speeding is illegal and increases the chance that you, another motorist or a pedestrian will be injured or worse. I love your blog, but this article strikes me as no different from discussing the economic benefits of any other illegal activity. Many are lucrative, but that shouldn’t become a rationale to engage in them.

16. Leslie says:

As a person who is always running late, I see spending \$26 to save 30 minutes as justifiable. However, this leads one to question the costs of poor time management.

17. Mark L says:

Looking at the time savings on a 200-mile trip, it just reinforces to me that speeding is seldom necessary unless you are traveling a long distance (say 500 miles or more). 10 extra MPH saves you 25 minutes on a 2.5 hour trip. Seldom is that really much of a difference maker.

18. Ryan says:

Now, I’m sure this start a wonderful debate for everybody screaming “safety”, but it’ll be fun…

The German Autobahn has no speed limit in many parts and higher ones than the US has in others. (With 80MPH being the recommended speed).

And it’s been found to be safer than the US Highway system.

I’m a firm believer that bad/irresponsible drivers kill themselves and others, not high speeds.

Now, city streets and non-highway roads should probably have a speed limit.

But don’t tell me that, for example, as I’m coming home from work at 11pm where traffic is scarce, that going 65 is keeping me alive while at 80 something terrible will happen.

19. Retired by Choice says:

Speeding becomes even sillier if you calculate the time savings alone for a shorter trip. Say you have a 20 mile commute or trip to the store. Driving 85 MPH vs. 60 MPH roughly saves you just under 7 minutes.

Is saving 7 minutes worth any risk at all, financial or otherwise?

20. Luke says:

This may be kind of a small detail to some, but one I stress quite frequently with my students, when you are doing calculations with a calculator/excel, you don’t need that many decimal places. in this case the two places to the right of the decimal are the only two that have any meaning the rest are not needed and just make the spreadsheet look cluttered. It may be the way the spreadsheet was set up by default, but it’s one of those things that bugs me.

21. Steven says:

Trent –

While your point is valid and well taken, I don’t like your method for generating “chance to get a ticket”. The curve should be geometric; driving 1mph vs 10 mph over vs 20 mph over, for example. The reason it matters is you have a higher-than-it-should-be cost for 1MPH, and way too low of a cost for 20mph. Good post though, and certainly has me thinking.

Side note: Is anyone else freaked out by Google’s ability to place ads? I’m currently staring at a “Fight your ticket” advertisement from TixNix just to the right of this box. :))

22. ChrisD says:

I agree with Ryan that on motorways safety is not an issue in the 55-80 MILES /h range. In the UK the limit on motorways is 70mph and there is a tacit agreement that up to 80mph is OK. Even up to 90 is probably safe enough (though not safe from tickets). Though this does depend on how motorways are built, how tight the curves are etc. In fact even on narrow country roads you are allowed up to 60 (though common sense should operate here) so the US limit of 55mph seems crazy to me. Thus my decision to speed would really be limited to financial not safety considerations as I wouldn’t feel I was being at all dangerous up to 70mph .

23. Jeremy says:

I applaud that Trent’s article was purely an academic discussion of the costs related to different styles of driving. Similar to evaluating the costs related to properly inflated tires, correct wheel alignments and such.

24. George says:

Trent totally forgot that in some states, driving over XX mph will get your driving license REVOKED if you’re caught. In Oregon, where I live, 100 mph is that limit. If you think your speeding ticket was expensive, just imagine what life is like after having your license revoked!

If you’re convicted of speeding too often, then your insurance rates will go up. That is not reflected in the tables.

I also agree with the posters who take issue with Trent’s linear “chance of getting caught”. You _will_ get pulled over for doing 75+ mph in a 65 mph zone if the police observe it. However, unless it’s a construction zone, you aren’t going to be pulled over for 70 mph in a 65 mph zone.

25. Kevin M says:

This entire post is flawed. While the discussion it generated may be worthwhile, as soon as you get to the first assumption, the entire argument falls apart.

Based on your first assumption, if one drives 82 mph for 24 hours (making the assumption that one could do this), then the chance of getting a ticket becomes 102% ((82 – 65) * 24 hours * 1/4). This is obviously incorrect.

Since all the calculations that follow depend on that chance of getting a ticket, the entire argument is incorrect.

26. Manshu says:

It’s rarely ever useful to speed and I guess it is not a rational reason. Last week, someone overtook me on a school zone and then I caught up with him on the traffic signal so we were both effectively at the same place. It’s more of an irrational hurry than a real reason for people to speed.

27. Darin says:

Interesting to see calculations like this. I’ve also pondered the benefits between multiple routes between home and work, where the longer distance route may be faster.

One other comment on safety. I would guess you are more safe if you are traveling the same speed as the flow of traffic, rather than much faster or much slower. This may not correspond with the posted speed limit. As some commenters pointed out, traffic flow is usually faster than the speed limit.

28. Maybe use some sort of exponential for the chance of getting a ticket for every 1 mph over the speed limit. It would probably be more ‘realistic’ than a linear approach. In the end though, speeding doesn’t seem worth it in most cases regardless of economics.

29. Shannon says:

I am continually annoyed by people’s assumptions that if they got a ticket, it’s because the officer was trying to meet a quota. My father and grandfather were lifetime police officers, and I also worked in law enforcement for several years. I can tell you that there is not a department out there that has any type of “quota” system in place.

Generally it is left to the officer’s discretion whether to issue a ticket, but sometimes departments will issue a zero-tolerance policy for certain types of violations and/or in certain areas.

Examples: We are having a major problem with speeders causing accidents on Highway X, so anyone driving over the speed limit on Highway X gets a ticket. Or, the residents on Elm Street have been complaining about speeders in their neighborhood, so we are setting up a speed enforcement zone on Elm Street.

Officers don’t have to meet quotas. Let that myth die.

30. Tom says:

Speed in and of itself is not normally the biggest safety problem. Present day vehicles are built to handle speed. Extremes and mechanical failures do come into play, but for the most part speed differences are much more of a problem.

It would be nice is we could implement speed targets instead of speed limits. (Weather/conditions make this difficult, but that’s another story.) On a freeway, where most drivers are traveling 65, a driver going 55 mph is just as much of a problem as one going 75. If you think about this, you know this as fact even though the emphasis is always high speed.

So… please do not keep repeating the same BS that you were presented. When you are told something, consider motive, consider experience, then think it through for yourself.

As far as the original article, I would submit that matching the speed of other drivers is safer than going the “speed limit”. Generally, if you are matching the speed of others, you chances of getting a ticket are not as great. You do lose some money in maintenance and fuel, but it’s worth the added safety. That’s not to say that you should match the speed of one idiot going 100 mph.

31. forumpostar says:

I recently read in The Consumerist that speeding tickets can negatively affect your credit rating, so that’s another cost.

32. Sachin says:

I agree with “Over the Cubicle Wall” and Steven that assigning a linear scale is deceptive. Thus, in my opinion, the cost between driving 64mph and 66mph as per your calculation is purely an artifact of this assumption.

Also the probability of getting caught should depend on the trip length. If the odds of being caught when I drive at 80mph on a 65mph highway for 10 miles or 1000 miles *should* be different.

33. Jon says:

Like Darin noted, I think you’re often much safer traveling with traffic, even if they’re going faster than the speed limit. Here in Atlanta, most of our highways have either a 55 or 65 mph limit, but for the vast majority of drivers, 75-80 is the norm. Even the far right lane is usually going about 70. Fortunately, that means you have to do about 90 to grab an officer’s attention.

34. Mark says:

I, too, must comment on the use of a linear equation to calculate the chances of getting a ticket. It uses the false assumption that all other things being equal (time of the month, construction area, school area, etc.) there is a steadily increasing chance to get a ticket the faster you go.

In most areas, I would think the following is true:

Driving 0 mph over the speed limit would result in a 0% chance getting pulled over (for speeding).

Driving 1-5 over the speed limit would probably never result in getting a ticket, but a negligible percentage should be used, call it 0.1%.

Driving 6-9 over the speed limit is where we start having to list some of those previously mentioned variables. If you’re in a school zone, yeah, driving 31 when the limit is 25 may get you busted during school hours. Defining the percentage on “may” is difficult. Driving 74 in a 65 on the highway is probably just as common as (and unlikely to get ticketed) as 39 in a 35. Since the article is primarily about highway driving, I’d put this percentage at 1%.

The next range that many ticket forms use is 11-20 mph over the limit (for pricing and points purposes). I think most people get pulled over doing this speed. 76-85 on the highway is going to get you pulled over. I’d throw out a percentage of 50% at this point. I can count on my hand the number of times I’ve driven past a cop doing this range of speed and NOT gotten a ticket.

At 21-30 over the limit, the only thing that will prevent you from getting pulled over is if you are, in fact, driving a police vehicle with your lights on. That is to say, the percentage chance here should definitely be 100%. Beyond 30mph, there’s not much point in listing a percentage…it’s going to be 100%

All of these percentages depend on the presence of a police officer that’s actually paying attention. I like Trent’s idea of increasing the percentage based on the amount of time you’re driving the speed. Again though, driving 67 in a 65 for 16 hours probably does not increase your .25% chance by a factor of 16. And on the other hand if you drive 90 in a 65, you aren’t going to make it past the first cop.

All that is to say that putting a specific percent on a thing like getting a speeding ticket is both futile and silly. The amount of variables involved in calculating such a percentage are too numerous to incorporate into an equation and lay people such as most of us who read this article would do well to remember that percentages can often be misleading and obfuscate the real nature of the concept being discussed.

Let’s leave the cost-benefit analyses to people that are trained to do them accurately.

35. MoneyEnergy says:

whoa…. safety was also the first thing that came to my mind… it’s got to be factored in. Lessons from my driving instructor: “Is it safe? Is it legal? Is it necessary?” The limits are there for safety reasons, too…. stay in the right hand lanes for slower traffic.

This is the most astonishingly irresponsible article I’ve ever read from Trent. Speeding kills people. I’m speechless.

37. Maureen says:

The potential consequences of speeding are much more serious than getting a ticket. There were over 9,000 speeding-related fatalities in the US in 2004. What is your life worth (or your child’s life worth)?

38. Candi says:

Well here in VA, the ticket does not really become economical for the police officer till you are doing greater than 9 miles over the limit. At that speed it becomes worth it to stop you. As this is the metro DC area, the drivers are insane anyway.

As for the folks who go exactly the speed limit because you think it is safe. . . .please remember to stay in the slow lane. If you get into the faster moving lanes going the speed limit you are very likely going to CAUSE the accident you were trying to prevent. Now if the whole US drive the speed limit it would be fine but this is the real world and folks do not. I have just seen way too many folks going 55mph change over 4 lanes to the left without increasong their speed and a near 10 car pile up happens behind them everytime.

39. Terry Lange says:

Why risk your safety, the cost of the ticket, the increased insurance costs,etc. Just do the speed limit and you reduce your chances of getting a ticket to zero… Why risk it? Is it worth getting somewhere a few minutes earlier? Why not leave earlier and plan ahead? If you are going to do the speed limit, stay out of the fast lane! Probably too much common sense in this comment!

40. Suzie says:

It doesn’t matter how much it costs. It’s ILLEGAL FOR A REASON.

What’s the cost of being responsible for killing a child? Or wiping out a family? Or being injured for life? Or killing yourself?

Speeding is a crime, you wouldn’t post about the cost/time/getting caught ratio of dealing drugs, or pulling bank robberies, so don’t do it for speeding.

41. Shevy says:

So, let’s talk about safety. First, freeways and most highways are built to be driven on safely at higher speeds than the posted limit. They just don’t advertise that fact. The reality is, they know people speed and they build in a safety factor for curves, etc. except in very mountainous areas, where they have additional warning signs posted. The big problem is, as always, the other drivers.

Some drivers drive faster than the posted limit and are in control. They don’t outdrive their headlights at night, or drive faster than is safe in bad weather. They allow several car lengths between themselves and the car ahead.

Other drivers are dangerous. They tailgate. They cut in and out. They turn their high beams on at night, blinding you, in an attempt to get you to switch lanes. They go too fast for weather conditions or for their car’s mechanical capacity or for their driving ability. Other drivers speed and allow themselves to be distracted by changing CDs or by conversations going on in their car.

You can probably tell the difference when you’re being passed by each of these types of drivers, but a police car stopped by the side of the road with his radar on can’t. That’s why the vast majority of tickets are based purely on the number of miles or clicks over the limit.

One other thought about safety. It’s often unsafe to go significantly lower than the surrounding flow of traffic, even when they’re all speeding. So, if traffic is fairly heavy and you’re in a 100 kph zone (62 mph) but most of the surrounding traffic is travelling 115 or 120 (71 to 74.5 mph) you may actually be increasing your risk of being rear ended by a tailgater or having someone cut you off. I suggest that you try to stay within 10 kph (5 or 6 mph) under the general traffic flow even if you don’t want to keep right up with them. It will also probably eliminate your chance of getting a ticket (even though you’re slightly over the limit), since the guy passing you is the one they’re going to pull over first.

42. Eric says:

First,

Next time, please take a few seconds to format your excel – I can’t believe you left that many decimals in. All you had to do was format it to dollars and it would have at least been readable – I just glazed over it, and I’m sure most others did also.

Second,

I’m a very financially minded person, but thinking in everything as “time cost” is rather irrational. To me, I don’t really care about what the hourly value of me not speeding is – because it doesn’t represent anything close to reality and isn’t the most important thing to be mindful of.

43. Jeff says:

Speeding isn’t simply about economics (time or money). People speed for different psychological reasons. Most of the real reason negate the happy-happy propaganda to reduce speeding. The actual reality of the cost is not what it seems either so some of the scofflawism is justified by practical realities.

Some people speed because they feel it’s one of the only places in their lives when they can “get ahead of everyone” and quite possible the only place they feel “in control” of their lives. What kind of society must we have to create that outlook?

Some people speed due to misperception of time and schedule importance – we humans been living “on the clock” as a lifestyle for 150 years (thank the US railroads) – our biology has not caught up so 1) we’ll always be bad at keeping on schedules – it’s not “natural” biologically, and 2) people are obsessive about keeping on a schedule are being profoundly unrealistic in requiring themselves or others to be on schedules.

Some people speed because simply enjoy the physical sensations of speed.

You could argue these are all cost and benefit inputs into the “speeding decision” as an economic decision.

Another seriously large part: all the benefits people have, including the intangibles above, are immediate and real (or perceived as real).

The costs as punishments are hypothetical and statistical in nature – when you speed you play the odds you will not be caught. Thus to correctly do the economics of speeding, you have to discount the costs by the probability of being caught or have an adverse result from speeding (crashing, killing yourself or someone else).

The costs of speeding are expectational or expected costs, not direct costs. If you have a 1-in-20 chance of being caught, then you have to discount the economic cost of punishment by dividing it by 20! The true downside risk is discounted by the probability of being punished.

This is closer to have people actually think about risks. However a problem arises because people are absolutely horrible about estimating risks in the first place if the true probabilities are less than 10% (1-in-10) or if the cost is more than 10x the amount of money they routine work with daily for their personal expenses. In other words most non-analytically based risk estimate are pure garbage and many analytical estimate are based on garbage assumption which result in garbage again.

This is why we worry about terrorism even though any individual American is 100x-1000x more likely to be injured or die from a mistake made by their doctor or by a fatal traffic accident. We are bad at estimating risk properly.

44. Patty says:

I agree with you wholeheartedly.

And to completely ignore the safety issue in his post. HOW DARE YOU be on the road and jeopardize my family.

45. andrew says:

I’m really curious as to where the “likelihood to get ticketed” percentages come from. Because according to the numbers Trent gave, if you drive 1 mph over the limit, for an hour, 400 times, you should receive a speeding ticket. I don’t know of a single police officer (here in the US) that would ticket anybody for going 1mph over.

Now, as far as safety is concerned. As Ryan pointed out, one of the safest roads in the WORLD has no speed limit. So if speed kills, and is so dangerous, then how does a road without a speed limit end up so safe? It’s because they ticket people for actually driving badly. Doing things like driving in the left lane but not passing; tailgating; passing on the right. Those are the REAL causes of accidents.

The NHTSA did a huge study on speeding and found that the safest speed to go is the speed of traffic, not the posted speed limit. Going 5 mph slower than traffic is EXACTLY as dangerous as going 5 mph faster than traffic.

That means that if you are “trying to be safe” and go the speed limit, and traffic is going 10 mph over the speed limit, YOU are driving more dangerously than anyone else. Even the CHP (California Highway Patrol) are telling people to just go the speed of traffic, and not the posted speed limit. This also applies if everyone is going 10 under the posted limit.

Its not how fast you are going that is dangerous, it is how fast you are going, relative to other cars. Another point, things like tailgating and swerving in and out of traffic are driving recklessly, NOT speeding. There is a huge difference.

That’s probably why Trent didn’t include safety into the article, its not a real factor.

46. Robert says:

I’m curious as to what things you factored in when coming up with the chance % of receiving a ticket, I know you mentioned that it varies a lot, but I think you have overestimated it largely.

Lets say that only 75/100 drivers go exactly 5mph over the limit, and the other 25 go the exact limit, which I think is overly optimistic towards the low side. Combined they would have a 75*(0.12)=90% chance of getting pulled over per each hour of driving. Hence, if I was driving down the road for an hour, I would see 0.9 cars pulled over on average. In reality I see maybe 1 car pulled over for every 10 hours of driving, and we have to assume that only a partial amount of those are for speeding infractions.

In my short life I have driven over 100,000km, and have never been pulled over, generally going 25% over the limit.

47. Scott C says:

Hi Trent,

Since you have the spreadsheet already set up, can you run the numbers for going under the speed limit?

48. Johanna says:

To those who are arguing that highways were built to be safe at high speeds: I don’t disagree with you, provided that you are talking only about limited-access highways. Where I live (the DC metro area) there are a lot of roads that look like highways from the perspective of a driver, but they are also used – and crossed- by pedestrians and bicyclists. This creates an unsafe situation. The drivers see visual cues that tell them “go fast,” and they forget all about the pedestrians and cyclists along the sides of the roads (who have just as much right to be there as the drivers do).

If you think that you are so busy and important that you are willing to risk your own money and life in order to save a little time, that doesn’t particularly bother me. But when you start risking the lives of other people who are a lot more vulnerable than you are, that does bother me. A lot. Very, very few people are really that busy and important.

49. Aristotle says:

There are a couple things to unwind here.

Speeding can (1) increase the likelihood that you’ll crash, or (2) it can increase the chance that, if you crash, you’ll die, or (3) it can do both.

A few of you have spoken against (1) (and therefore (3)); fair enough, though I’d love to see some actual numbers cited. But what I haven’t heard is someone saying that driving faster helps you when you get in a crash–and that is because, no matter how good a driver you are, it is simple physics that the faster you drive, the more likely you are to die if you get in a crash.

(See http://www.tfhrc.gov/safety/speed/speed.htm. Key quote: “…a 30-percent increase in speed (e.g., from 50 to 65 mi/h [80 to 105 km/h]) results in a 69-percent increase in the kinetic energy of a vehicle.” And let’s guess what happens to that energy when you go from 80 mph to 0 in a second…)

Just another thought: I doubt Trent thinks the best argument against speeding is the financial argument he’s made here. He’s got kids, is surely aware of the safety implications, etc… So I think his take here is more a function of the fact that this is a PF blog than that he considers this topic with wild disregard for the safety factor. (My first comment w/r/t his omission of safety was just picking up on the fact that I think safety can also be put into dollar terms, if you want to make the PF argument….) This is a PF blog, so Trent’s making the case in \$\$\$. If it were a more personal blog, I’m sure he’d mention the human cost of high-speed crashes, etc.

50. Katie says:

The cost of a ticket also varies with your age and the state you live in and are insured in. My teenage brother got some tickets that sent his insurance premiums sky high. My parents were also penalized for any infractions, but not nearly as harshly.

51. Dave says:

Your method for calculating likelihood of receiving a ticket is invalid.

The correct metric needs to include miles in the denominator eg: likelihood/mile.

As you’ve currently structured it, the likelihood of getting a ticket is the same whether the drive drove 1 mile or 3000.

Okay, I’m getting a little irritated by all of the people calling this article irresponsible. Yes, speeding is dangerous and illegal, that’s why I don’t do it. I watched all the videos they showed us in driver’s ed of mangled up dead bodies being pulled out of cars that were driving 100+ mph. Heard plenty of stories about kids being killed in accidents. So did a lot of other people.

For me, and a lot of other commenters here, life is more important than money. Those driver’s ed videos and stories have an impact on us. Unfortunately, there are a lot of people out there who seem to think that money is more important than anything else. Show them all the statistics you want, show them all the gorey driver’s ed videos you want, they won’t slow down. Maybe they think they’re invincible, maybe they just don’t care about all of the other people their endangering. Either way, your safety argument is falling on deaf ears. But these people still endanger our lives, so let’s try a different approach to get them to drive more safely. Hit them where it hurts, in their wallet. Unfortunately that’s the only place it hurts for some people.

I’d like to see info like this post shown in driver’s ed and traffic school classes alongside all of the accident scene videos. Hopefully the people who couldn’t care less about all the innocent children they’re endangering will care more about their wallets.

53. almost there says:

Looks like Trent had too much time with the spreadsheet. What didn’t get factored in besides the irresponsible action of speeding to self and others is the cost and amount of time it takes to be cleared from your insurance. My company keeps it on for 3 years per incident with higher rates. So it isn’t just a matter of paying the ticket.

54. WilliamB says:

After reading this and following the math, there was one thought uppermost in my mind, strongly and loudly.

Geek!

(PS – a complement in my vocab.)

55. Sara says:

Very interesting. I love these cost analysis posts. That said, I think it’s unrealistic to assume a linear relationship between speed and chances of getting a ticket. It is probably more like an s-curve.

I don’t understand why people are so upset about the safety factor. For one thing, your conclusion discourages people from speeding! And I don’t know how they would propose to factor safety into the cost calculations, as that would be a little beyond the scope of this blog. I think it’s fair to say that the calculations stand with the assumption of driving safely, even if driving above the posted speed limit. Of course, that wouldn’t cover driving 120 mph — that’s obviously unsafe in any situation, and I doubt you would ever suggest anyone drive that fast — but I guess you extended the calculations just for the sake of information.

56. DB Cooper says:

You’ve been thinking about this…a lot? Sounds like you’ve got waaayyyy too much time on your hands. What are the calculations on the value of your time spent thinking about the cost of speeding and the worth of the time that you lose if you get a ticket vs. what you gain by getting to your destination sooner…wait – what is my time worth as I sit here contemplating the value of your time…gotta go!

57. sylrayj says:

I think that if one wants to know if speeding is worthwhile, their best bet would be to talk to truckers, who are on the road steadily and regularly. My uncle-in-law told my husband that he did try speeding when he was younger, but it takes its toll on the truck, on gas, etc. I wouldn’t be surprised if there’s a toll on one’s body, too; the anxiety of weaving in and out of traffic hoping that the open spot doesn’t abruptly close, and the fear from near-misses. There are probably many people who have to find out for themselves, how taking risks and lane-hopping gets them a fraction of a second farther ahead by the next street light – maybe the “competitive spirit” was sated, but we’re always glad when they or we go a different direction so we don’t have to drive near an ‘accident waiting to happen.’

When you drive in a way that varies from what the drivers around you are anticipating, you bump your chances of an accident. Sometimes you’ll need to drive faster to be consistent. Be aware of your own ability to control your vehicle, your stress levels, the traffic around you, and please drive to stay alive.

58. Amy says:

There’s one factor that has a HUGE effect on your numbers, Trent. The number of passengers.

In a car with just the driver, your numbers are correct. In a car with multiple people, costs stay the same, but the time savings are multiplied because everybody arrives earlier.

So, if there are three people in the car, going five miles over the speed limit assumes an hourly rate of \$13 per person.

Secondly, for everyone screaming about safety, please consider that the maximum speed limit on the Interstates varies from a low of 60 to a high of 80 by state. All interstates are built to the same speed and engineering standards, which suggests that there are factors other than pure safety considerations that are determining how speed limits are set.

Speed limits are set because a line has to be drawn somewhere, but it’s hardly the case that driving 65 is safe, while driving 70 is not safe.

59. Stephanie says:

What? Cops have quotas!?!?! ;) They will NEVER admit that they do!

I will be really candid here and admit that as a impatient speeder, when gas prices got very high last summer… I slowed down! I knew I would stretch more miles out of the tank.

Everyone has different values. I absolutely HATE being late and will speed sometimes to avoid lateness. Other people don’t mind or are constantly late as it is. I applaud Trent for the subject of the article as it has so much to do with personal finance which is what the site is about!

60. Charlotte says:

Ryan (#13), have you actually ever driven on a German Autobahn? They are built quite differently from US highways, much wider, much straighter, avoid hills wherever possible. Comparing safety of the two is like comparing apples and oranges.

And the “unlimited speed” on them is a myth for a large percentage. Most of them limit the speed to 130km/h (roughly 80mph); only few stretches are truly unlimited.

61. Ryan says:

No, I have not. I’m 17 and haven’t had the luxury of traveling overseas.

I disagree that it’s apples and oranges. Both are highway systems and while I know that the autobahn was designed specifically to accommodate high speeds, surely there are stretches on US highways that could do without a speed limit.

As you pointed out, many are limited to 80mph. Few if any US highways (in my state at least) allow speeds that high…but yet, I’ve driven 80mph before and never had any problems controlling my vehicle. If there’s a sharp curve, you slow down. It’s not hard.

And for a true Apples to Apples comparison, one study found that accident rates were the same in limited sections of the Autobahn and in unlimited sections.

Everyone screaming “It’s ILLEGAL FOR A REASON” has me cracking up. I suppose that you wouldn’t have dared take a sip of alcohol in 1925? But you definitely would have in 1934?

62. JorgenMan says:

Trent,
I really can’t understand where your “hourly earnings” numbers came from. For example, you say, “Your hourly earnings from driving 65 instead of 70 is \$38.91”, but \$38.91 is more than the total cost for the three-hour trip.

65 mph:
(\$20 average trip cost) / (3.08 hours) = \$3.29/hour

70 mph:
(\$28.55 average trip cost) / (2.87 hours) = \$9.95/hour

This comes out to \$6.66/hour cost to drive 70 instead of 65. Your \$6.66 buys you about 4 minutes in that hour, since you drive as far in 56 minutes at 70 mph as you do in 60 minutes at 65 mph, including average delays for tickets.

63. David K says:

I live in Southern California so I think that your chances of getting ticketed are much lower then that. I’ve driven 50,000 miles so far and probably average 5mph over the speed limit. By your calculations I should have averaged 10 tickets! But I’ve never even gotten pulled over. I know it’s incidental but it’s still very off.

Great blog, btw.

64. reulte says:

Stephanie (#38) … uh, being late or speeding aren’t the only options, you know you can always start out at a reasonsable time to get to your destination.

65. Mardi says:

Sooo funny!

66. K says:

Another thought is that \$150 to save an hour when you have 2 kids under 5 in the back seat might just be worth it (safety always in mind of course).

67. Stephanie says:

@ reulte,

That is what I aim for. But I don’t live in a perfect world and things happen that you can’t always predict that might slow you down.

I never said that “uh”…being late or speeding were the only options I utilize.

68. Mike says:

69. MattJ says:

I agree with others here that your estimate of the likelyhood of getting a ticket is odd. In my view you have a near-zero chance of getting a ticket for about 1-8 mph over the limit, and it increases until around 15 over, after which your chances of getting a ticket are approximately equal to the odds that you pass by a cop, which has nothing to do with how fast you’re going. Between 8-15 mph the probability really hinges on whether you’re moving with traffic or not.

The cost estimate you’ve come up with is also odd. High-mpg tickets are going to be way over \$200, and your table goes well over 100 mph. If you get a ticket for doing over 100, there’s a good change you’ll be facing reckless driving charges. Now you’re losing your license, hiring a lawyer, and maybe doing some jail time. That’s expensive.

All that said, safety should be the priority.

70. getagrip says:

Simple physics, kinetic energy is based on your velocity squared. The difference in energy between 65 and 75 mph is greater than what we would intuitively perceive. So if something goes wrong (sudden swerve, blown tire, road debris, etc.) you and your vehicle are less likely to deal with it and you’ve put yourself and those in the vehicle with you in more danger and at higher risk of injury/death.

Speeding is only one symptom of people “needing” to get somewhere “now”. It often goes along with tailgating, cutting folks off, passing in blind spots or other dangerous actions, etc. which usually causes the accidents that slow everyone down. Also its the folks who get in the speeding habit on the long morning commutes who take it with them when they go to get gas or are late taking little Joey to his soccer practice. They think nothing of going 55 mph down a 30 mph street never thinking they are driving past their ability to see past the curve ahead.

Part of that stems from getting so used to driving so fast, that when you get off the highway 55 seems slow and safe, so they’ll go that speed thinking they’re safe. Sure, if no one else were anywhere near the road you could probably drive 70 mph on that 30 mph road with no problem. Except people are pulling out of driveways, crossing the street, riding their bikes, etc. So they put all of us at risk in our neighborhoods at all times of the day or night for what, thirty seconds to a minute of getting there faster? Assuming they don’t get caught at a light? For me it’s not about saving money so much as those jerks tailgating me at 70 mph on a highway or 40 mph down a residential area are essentially taking over a ton of metal, plastic, and flesh and threatening me to do what they want because they feel they deserve to get somewhere to save themselves a few seconds. How would that jerk feel if I walked down the street with a loaded shotgun pointed at his back with my finger on the trigger? He can trust me, I’m not going to accidently bump him and pull the trigger. I mean, I’m just walking here, right? Hell, you’d tell someone to screw off if they were walking a foot behind you without the gun because they were invading your personal space, but somehow we figure it’s okay to threaten people with our cars at speeds that can kill and seriously injure us just to shave a couple of seconds off our travel time.

When I took my daughter driving with her permit, it’s amazing the number of people who will actively tailgate and get pissed. Mothers with babies strapped in, Young adults texting about us to their friends, Fathers cursing us with their daughters in the seat next to them, grandparents who you’d think would know better, all of them were actually outraged that we were driving at the speed limit. The only saving grace for my daughter was letting her know that even if you go above the speed limit, it won’t matter, some jacka\$\$ will still ride up on you, no matter how fast you’re going. So you may as drive at the speed you’re comfortable at, because you can’t make ’em happy.

71. Donna says:

I learned early on that speeding can sometimes put you in a place where you would not have been had you been doing the speed limit. I was doing the speed limit (55) on a busy interstate, in the slow lane, when a car zoomed by doing about 80 in the middle lane. There was a semi about 1/4 mile ahead who hit his brakes because of something in the road and jackknifed. The speeding car had advanced right next to him at the time and got involved in the fiery crash and died, as did the driver of the semi. I was still far enough away to stop to avoid it all. Had I been speeding, I would have been involved and maybe dead. The interstate was shut down in that direction for 24 hours while they cleaned up the mess. Speeding may put you in the wrong place at the wrong time!

72. Michael says:

I drive the speed limit because at 65MPH, I can read a book on the highway. If I drive an hour on the highway, i get about 55 minute of reading done. If I drive, say, 75, I can hardly read at all, so driving faster actually costs me nearly an hour. (Assume when I arrive doesn’t matter and I needed to read anyway.)

73. Kate says:

This is a little off topic. Even someone who doesn’t normally speed can get entangled in speed traps if they are not super alert to changes in speed limits. I have found this website useful: http://www.speedtrap.org/
I looked up the known ones around my own area and they are all there, along with a few that I wasn’t aware of. I also looked up the routes that we use to go visit relatives and now I know to be extra cautious when traveling through those areas.

74. almost there says:

A former commanding occicer I worked for would always arrive on time for any meeting or event. He would chide the people arriving later than him by saying “If you can’t be on time, be early”. They got the message. I try to live to that rule even 10 years later. One of my peeves is arriving before an appointment and having to wait past the scheduled time. So, no, speeding is not necessary if you plan your trip. And if you will be late, BFD.

75. Rosa says:

You left out the emotional cost of dealing with a seething passenger who can’t stand being passed and will never let you drive because you’re too slow and then becomes angry and stressed out because they hate driving in heavy traffic (all that waiting! it’s HORRIBLE!)

I usually stick about 8-10 miles over the speed limit, and in a lot of places we drive that’s well below the prevailing speed of traffic.

76. GayleRN says:

Obviously this whole discussion is from people born later than the 1973 oil crisis. When I learned to drive in the 1960s pretty much any paved road of reasonable straightness was posted at 70 mph. The reason everything was suddenly reduced to 55 mph was to save gas. Period. Eventually there was a reduction in fatalities related to speed. Therefore it was not that difficult to figure out that 55 would remain the speed limit in most places with the exception of divided highways ie interstates. So that eventually got changed back to 70 because nobody was actually driving 55 on an interstate anyway. It was all controversial at the time, but now a whole generation has grown up not knowing any differently.

Around the same time seat belts became standard equipment on more cars and eventually usage was required. That also contributed to a reduction in fatalities. When I learned to drive most cars didn’t have seat belts and infant seats had yet to be invented.

When you have an opportunity take a look at the speedometers of some older vehicles. Yes they really could hit those numbers.

77. Eli Sarver says:

You don’t “earn” anything by speeding or not speeding. If driving the speed limit is the norm, then you can only spend more in gas or tickets by going over the limit.

If you were modifying your habits from excessive speeding, then it would be “saving” not earning. Nobody is going to be paying you for it.

78. TJ says:

@ Donna,

That arguement makes no sense. I could just as easily say that by speeding, I passed that truck sooner and therefore never even saw the accident because it was behind me.

Highways are built for the speeds that people travel, not the speed limits posted. When you pass into different states, the interstates are built exactly the same way but the speed limits change. Therefore, the speed limits (within a certain range) are there for purposes other than safety.

Gosh Donna, that sounds like an accident that happened in my hometown in the last year… Can’t remember if that was before or after another accident on the same section of the freeway. I think a garbage truck was going one way, another truck was going the other way, somebody got cut off and one of the trucks jacknifed, went through the center divide, and hit the other truck head on. I don’t remember if the driver of the garbage truck survived, but the driver of the truck going the other way died. Ironically enough, the other truck was hauling coffins… Freeway was shut down for hours in both directions…

80. Leah says:

I love Kathryn’s response. Driving slower (after two tickets) was also very good for me. I notice so much more, and I also get less stressed about driving. My new attitude? I’ll get there when I get there, and it’s not worth fussing about. I try to leave myself a cushion when I can, but I also cut myself slack when I’m running late.

My real transformation moment was during a safe driving class after my second speeding ticket. They showed a video with a mom chatting on the phone and a kid sitting on some steps with a backpack. All of a sudden, the mom goes “oh, no, I’m late to pickup Suzy!” She speeds out of the driveway and towards school. Then, the video cuts to Suzy, and a voiceover says “Suzy’s mom was late to pick her up. Now she’ll never arrive. Better late than never,” as the video cut back to an accident scene. After that, I really decided that I’d rather be late than dead.

Plus, my gas mileage alone is financial incentive enough for me :-)

81. Jim says:

Trent,

I agree with your conclusion. As others have pointed out insurance costs are going to weigh much heavier than the ticket itself.

You said: “you have 1/4% chance of receiving a speeding ticket for each mile you’re over the speed limit for an hour.”

I’m curious whether you got the 1/4% figure from? Was that based on some math from statistics?

It wouldn’t be linear function. The liklihood of getting a ticket going 120MPH is much greater than if going 66MPH. But I can see if you treated it as linear for discussion sake to keep it simple.

Jim

82. The \$185 I spent last year on a top of the line state of the art radar/laser detector has been money well spent. It has NEVER missed any kind of speed trap and it does keep me aware of how fast I am driving–the main reason I bought it as opposed to being a speed demon. I drive a ticket magnet and even though I rarely speed, even 2-5 over will get me tagged in this car so the beeping of the detector has reminded me on many occasions to make sure I’m NOT speeding!

83. guest says:

I wanted to add that in California, the fine for speeding goes up substantially when you are more than 16 mph over the speed limit. I believe this is why you can drive 80 (65 zone) past the speed traps and not get pulled over. The cops are waiting for a higher ticket. They may not have ‘quotas’ per se, but since my city’s tax revenue has been dropping substantially, there have been a LOT more police out doing radar and writing tickets. Speeding tickets are a big money maker for government…it’s not solely about safety.

84. Sharon says:

A tire in the road at 55 MPH is probably avoidable. At higher speeds, it isn’t. A broken tie rod in that older car you are so frugally driving at 65 MPH = fatality or serious injury. A large animal on the road, or a small one you want to avoid? The slower the better. The more space between the car in front of you and behind you, the better. You should never be more than two seconds behind someone, and you should be 4 seconds. Forget car lengths!

The big problem with speeders, tailgaters and other horse’s asses is that they foolishly assume that there won’t be any problems on the road, or with other drivers. That is why the state offers those “lame defensive driving courses.” Next time you take one, you might want to try actually paying attention. What you learn might just save your life, and the lives of others with you.

I do pay attention. I try to analyze traffic as far ahead of me as I can see and as far behind me as I can see. I can anticipate abrupt lane changes, two cars deciding to enter the same lane at the same time, realize that the ball in the road means that there might be a child (of any age!) following it, etc., and I make my driving decisions accordingly. I decide where I will head in the unlikely event that I see a head-on collision coming. I mostly SLOW DOWN and leave space. I identify safe(r) alternatives on the highway.

Tailgaters get my hazard lights in their faces. If that doesn’t work I have mastered making my brake light flash at them without actually braking. Sometimes I roll down my window and point out that there is another lane next to me. (I use my index finger almost always.) As a last resort I will slow down gradually.

Most of the time is is someone driving while oblivious (usually on the *#&!@ phone!)
Some of them are aggressive jerks; I have elected to get off the road on occasion, during which time I call the State Patrol to alert them.

In any driving situation, DRIVE! Don’t speed, don’t be aggressive, and keep in mind this old quote: “I’d rather have them complain that I’m late than say “Doesn’t she look good” a few days later at my funeral.

85. J says:

“55 is fast enough to kill ya but it’s slow enough to make﻿ you think you’re safe”

Speed limits in the US are a joke. Most are set artificially low, lower than what the road was designed for. Back before the Arab oil embargo in the 70’s they were actually higher. You know, before antilock brakes, airbags, better tires, better brakes, crumple zones, seatbelt laws, better headlights, child seat laws, run flat tires, and probably a bunch of other safety equipment we all take for granted.

From the comments on this blog, you’d think that someone going 66 MPH is coming straight out of a Mad Max movie and coming to kill your children. Lighten up, people. If the self-righteous people would actually yield to the faster traffic (translation: if someone is tailgating, flashing their lights, motioning for you to change lanes and then passes you on the right, you are going too slow), there would be less stress on the highways. In other countries, people stay in the slow lane and get over when faster traffic approaches. And they do this at (gasp) higher highway speeds and have (gasp) less fatalities per mile than here in the good old US of A. Many other countries also have driver training that isn’t a joke, as well.

All you frugal safety people going into hysterics please stay right, I’ll be in the fast lane. You do your thing, I’ll do mine. I’ve been exceeding the speed limit for some time and haven’t gotten a ticket since the mid-90’s. I stay alert, watch traffic and PAY ATTENTION TO THE ROAD. I don’t own a radar detector, CB or anything like that. I also don’t talk on the phone while driving, either.

86. Aaron says:

“At 21-30 over the limit, the only thing that will prevent you from getting pulled over is if you are, in fact, driving a police vehicle with your lights on. That is to say, the percentage chance here should definitely be 100%. Beyond 30mph, there’s not much point in listing a percentage…it’s going to be 100%”

Clearly you’ve never driven on I-80 across NJ during morning rush hour. Prevailing speed is 85-95 mph in some parts. (even back when the speed limit was only 55)

It’s certainly not 100% — in HS, my best friend’s dad would do that morning commute daily, driving at those speeds, and he received a negligible number of speeding tickets (1, maybe 2 year).

The calculation, as many others have noted, should be a geometric progression based largely on the difference between your speed and the prevailing speed. You are far less likely to be pulled over for going 80 if everyone is driving 80 than you would be for going 80 if everyone else is going 70.

Based on my experience, Trent’s chance of getting caught appears to be way too high. I typically drive about 8 miles over the speed limit. I’d estimate that I’ve driven 90,000 highway miles over the past 10 years, or about 1,230 hours at an average speed of 73 mph. Based on Trent’s formula, I should have received 25 tickets over the last 10 years (0.25% speeding ticket / miles over per hour x 8 miles over the speed limit x 1,230 hours). I’ve received 0 tickets and 1 warning. If my one warning had been a ticket, Trent’s rate is still off by an order of magnitude. Maybe I’m just lucky.

88. DK says:

I normally agree with you but your assumptions are off.

It’s not a linear function at all, and as long as you’re traveling with prevailing traffic and not in the far left lane, you literally won’t get a ticket for less than +10 in most cities…the cops have real crime to enforce.

Driving 85? Yes, stupid. But if everyone drove the speed limit this world would grind to a halt, economically and otherwise.

89. Kate says:

I try to keep my speed between sixty-five and seventy, but I’m doing that for reasons of fuel economy. (And when I have the time, I set the cruise control at 65.) But speed limits in my state are 75, so I am consistently passed.

It bugs me, as I enjoy driving faster. (And I am a safe driver, so I don’t worry too badly about the speed factor there.) But I’m worried enough about our over-dependence on petroleum that I’ll put up with the slower speed.

If we ever get a hybrid, though, my speeds may go back up!

90. Billy says:

You did not take changes in insurance into account. My father got a ticket for going 70 in a 55. His ticket was \$150, but his insurance increased \$500 every six months for three years. Based on this experience, going more than five or so over is extraordinarily expensive.

91. J says:

@Kate — speed differential is what causes a lot of safety problems. You create an obstacle that’s probably 10-20 MPH slower than the remainder of the traffic flow. While you may be saving gas, it’s possible that the people who have to slow down and accelerate around you are wasting more.

Just keep up with traffic and everyone wins.

92. Dan says:

You are forgetting about the “sweet spot” in engine performance.

Every engine has an optimal speed they run at, meaning, as you increase speed/power, you actually use LESS fuel.

For most cars this “sweet spot” is somewhere between 40 and 60 miles per hour. (Usually the point where you’ve topped off the acceleration- if you’ve ever noticed when you get to “top speed” and slightly let off the gas, the RPMs drop a bit, but you maintain the speed)

So, for basic cars, it’s best to go slightly UNDER the speed limit!

However, you can adjust your car’s computer (well, you probably need a technician to do this) so that it gets a “sweet spot” at higher speeds.

Mix that combination with better tires, oil, level loading, and all that stuff and one can actually get better gas mileage at higher speeds!!!!

Your assessment is pretty fair on the probability of a ticket, though, most folks know which roads have a better probability of ticketing (or at least where the police sit) and they can also invest in a high quality radar detector or jammer.

@Sharon – Right on. I wish everyone drove like you. I suspect a fair few of the tailgaters you mention are posting on this blog btw :-)

94. Kate says:

for J, comment #91 You create an obstacle that’s probably 10-20 MPH slower than the remainder of the traffic flow.

Sorry; I left out a critical detail! MOST of my driving is between our small rural settlement and town, via a rural stretch of interstate highway. Traffic is seldom heavy enough for one slow driver to make that much difference. And, what with horse trailers, and pickup trucks towing vehicles or trailers, and RVs driven by snowbirds, my speed’s not even all that unusual! :)

When I go into an urban area, or when I’m on a two-lane road, I do go with the flow.

95. Bill in NC says:

I hope those posters driving more than 10 miles over the limit also remember to buy an umbrella liability policy.

After any accident, authorities will download the data from their vehicle’s black box, which will then be used against them in both criminal and civil actions.

Like it or not, the ones speeding the most will be assigned the blame for the accident.

96. J says:

@Sharon – If you are not in the right most lane and are pulling the stunts you mention, you are being the horse’s ass.

Not to mention, of course, that such behavior (hazard lights, braking, slowing down, pointing out the window, etc) is aggressive driving in and of itself. I used to pull such stunts, myself, now I just yield to the faster traffic and get on with my life. I’ll let people who want to go faster go on, let the police deal with them.

After driving in England I saw how people maintaining lane discipline actually reduces road rage and increases traffic flow. There were no tailgaters because the people who were blocking those who want to drive faster (gasp) GOT OUT OF THE WAY. Even better, in Germany, you can be ticketed for failure to yield! Not so in the US, where there is some perverse “I own this left lane” attitude.

97. Mike says:

I took my driver safety course from a State Trooper who was an accident reconstruction specialist. As I remember it, he stated that accidents are not caused by speed per se. They are caused by differences in speed. In other words, if traffic is averaging 65, drive 65 to be safest. If traffic is averaging 75, drive 75 to be safest. So in my mind, I also need to figure in the possibility of not arriving at all, and adjust my speed accordingly.

98. linlu says:

All speeding does it get your there 2-3 minutes faster. We have confirmed this via our GPS unit which is extremely accurate on local trips. For long trips in the 200+ mile range, the difference was 10 minutes.

I read only the first few responses, so someone may have already said this. One thing I notice is that when someone speeds in town it shortens the gap between cars that drivers have when attempting to cross or turn into the street have. What happens is that after waiting longer than usual due to the speeders that close the gaps too soon, these people often take chances and make highly risky turns or crossings.

I also make it a point to stay in the right lane on the freeways. In town I get over to the lane I will be turning from to avoid doing an idiot lane change at the last minute.

I have little tolerance for speeders in town, but I don’t block them or do anything to get them back, other than say to myself “Bubba can’t read a speed limit sign”.

On the highway I keep up with traffic unless it is going faster than I deem safe and stay to the right. Usually traffic is doing about 5 miles over.

99. Chris says:

I read the first 30ish comments and I don’t think anyone mentioned this particular glitch in Trent’s equation that actually strengthens the case not to speed:

If you get pulled over going 85 somewhere along your trip, I’m pretty certain you’re not going to pull back on to the freeway going 85 with the highway patrol officer pulling on behind you. Thus, your time lost is not just the 10 minutes from actually receiving the ticket; it’s also the time lost from not being able to continue at 85 mph. The earlier a ticket happens on your trip, the worse your time loss. Yes, you can chance speeding up to 85 again; but, who does that after already getting a costly ticket?

100. reulte says:

Stefanie (#67) You are right. This is hardly a perfect world and I will hang my head in shame (I’ve actually done 119 mph so it isn’t like I’m blameless!) If someone is occasionally late there’s usually a good reason and they’ll give a heartfelt apology and usually mention why. If someone is consistaly late — well, then they aren’t preparing correctly and/or they aren’t being considerate of the person waiting. Someone asked a famous race car driver if he had ever received a ticket and he said, “No, I always make sure to leave home early”.

Sharon – You should never be LESS than 2 seconds behind someone. But you’re right that 4 is better. Sometimes, however, once you have a 4-second leeway, someone cuts in! Very aggravating!

Trent – I think your numbers for “chance of getting a ticket” are skewed because they don’t and can’t take into consideration various factors such as place or time or prevailing conditions. For instances, school areas during the flashing light time – your chance of getting a speeding ticket go up astronomically. Ditto if you’re in an area that is considered a speed trap. On the other hand, I’ve gone 119 mph in deserted areas such as I10 between Tucson and Phoenix, AZ. And, it used to be that in Nevada speeding was less of a problem than drunk driving so the police seeing you go 100 might let you pass as long as you didn’t weave back and forth.

Usually, I drive what the road and my car will allow but it also depends on where I am. I start off below the posted limit due to unfamiliarity and work my way up from there. In Germany, I stayed below the limit — radar cameras are posted everywhere. Where I am now, I stay below the limit — the pedestrians are dangerously suicidal. A few months ago, a pedestrian walked into my car as I was waiting for a light to turn green!

101. David Mays says:

The only comment I have is about your suggestion to set the cruise control at the speed limit.

Many times, it is in fact less fuel-efficient to use cruise control, especially in rolling terrain or variable traffic.

Cruise control will be sure to maintain your full speed up a hill, whereas with careful driving you can slow down slightly while going uphill, relying on your car’s momentum more than fuel, and this saves a very noticeable amount of fuel.

In variable traffic, you need to watch what’s happening ahead and adjust speed accordingly to keep from having to slow way down and subsequently resume full speed.

102. steve says:

@ ryan

“As you pointed out, many are limited to 80mph. Few if any US highways (in my state at least) allow speeds that high…but yet, I’ve driven 80mph before and never had any problems controlling my vehicle. If there’s a sharp curve, you slow down. It’s not hard.”

You would probably shocked at the sharpness of a curve that can be taken at 80mph by a driver who is skilled at cornering. The average car has a stunning amount of cornering ability in the hands of a driver who understands and can control its front to back and side to side wheel balance, which affects tire patch size and . If you ever have the chance to be the passenger of a skilled driver on a track you will see. Even on the road, where you would normally only want to use 70-80% of that cornering ability, it is a lot a lot a lot. Of course, there’s lots to know before you can successfully corner at high speed and most drivers don’t have the knowledge and background to do it, but really you would be shocked. Actually most drivers don’t really have many skills or much knowledge at all to tell the truth. You have to go out and get them as they are not required under our current licensing system.

103. steve says:

@ sharon

yes if someone is tailgating you the most effective thing thing to do is to very subtly slow down by coming slightly off the gas, almost so subtly that you wouldn’t notice, and they will go around you very soon. As long as you don’t let on that you are slowing down on purpose, they will try to go around you due to impatience. In other words, don’t brake, but just ease down the speed by coming off the gas.

it’s funny how you can actually control what the tailgaters do in most situations.

104. Matt says:

It always amazes me how no one reads previous posts, but instead rant on about something that’s been posted a dozen times earlier already. It’s exactly this lack of foresight that has people thinking that speeding is the answer. So few people analyze the road beyond the car in front of them. So many opinions in this post, but only 2 posted facts (and one was a repeat of the first, lol). Instead, everyone tries to argue Trent’s assumptions (which he already said were just there for simplification purposes), overlooking the point that it IS stupid to drive well beyond the speed limit. Not EVERYONE drives 85-95mph on a 55mph road, anyone who tries to claim that as a fact is beyond stupid. Ugh, you people…

105. Garrick Rorapaugh says:

A couple points:

1. With respect to safety: Higher speeds causes increased stopping distances and higher impact forces wich will result in higher accident rates and higher fatality rates. So in general, driving slower is safer than driving faster.

2. But #1 isn’t absolute! There’s an increased risk of accident between cars traveling very different speeds on the highway. If you drive 35 mph on the thruway where prevailing traffic is moving at 75 mph, you are much more likely to be involved in an accident. So you should try to drive roughly the same speed as the surrounding traffic, but keep to the lower end of the range of speeds of the surrounding cars because slower is safer (see #1).

3. Before estimating the cost of a ticket, it’s worth taking a look at the fine schedule for your state. In Massachusetts (I believe most other states are similar), there is a base \$50 fine for the first 10 mph over the speed limit plush an additional \$10 for every additional mile per hour over the speed limit. Even if you are not cynical about police officers’ motives to maximize there take per vehicle stop, it’s pretty clear that the law cares much more about going more than 10 mph over the speed limit than going less than 10 mph over the speed limit.

I always keep these three points in mind during highway driving and in my area (Boston, MA) this leads me to drive between 0-10 mph over the speed limit. Driving faster than that increases the risk of traffic tickets and accidents dramatically. If I’m impatient, or in a hurry or have a long drive ahead of me, I drive near the high end of that range. Otherwise, I keep it near the low end.

106. Greg says: