Last week I talked about how fast is fast enough, and that one of the easiest ways to save fuel was by simply going slower. Well rejoice! Apparently all of America heeded my advice, and American drivers, on average, drive below the posted speed limit.
Ok, obviously this has nothing to do with me. According to Tele Atlas, the mapping unit of GPS maker TomTom, anonymously collected data from millions of GPS devices shows that most Americans are driving under the speed limit. So why don’t I get that feeling when I am on the highway?
According to an Autocar UK story, Tele Atlas says that no state tops 70 mph as an average highway speed. The fastest highway in the country is the stretch of I-15 between Utah and Nevada, with average speeds of 77.67 mph, even though the speed limit is 80 mph. This baffles me. I-15 is a road that pretty much runs through mostly desert. Why wouldn’t you go the speed limit?
The state with the fastest average speed was Mississippi, whose drivers went exactly 70 mph. Which is the speed limit. The slowest area of the country, surprisingly, is Washington D.C. which comes in at a sluggish 46 mph. Maybe because of all the Beltway traffic?
I honestly don’t know what to make of this data. In my own personal experience, when I drive the speed limit (65 mph here in CT) I get passed by everybody but the little old ladies in their Buicks. What about you? In your experience, do people drive slower, faster, or at the posted speed limit?
Source: AutoCar | Image: Ltljtlj
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About Christopher DeMorro
The strech of I-15 is only 2 lanes each direction. There is often a lot of traffic and it can slow to a crawl. They are also doing construction on that highway to make it more lanes. This will aliviate some of the congestion, but for now it just causes slower speeds. I for one travel about 40 miles a day on I-5 and I generally am going between 50 and 65 depending on if it up hill or down hill. I pay attention to my throttle position and not the speed. The speed limit is 65. I getting 40% higher than the EPA estimates my car should get as a combined city / highway mileage. I am constantly being passed, but the savings are more important than the speed.
the answer is that you must understand the difference between the mean and the median. If 90% of the drivers are driving over the speed limit, but one old person in a Buick is driving EXTREMELY slowly, say 30 mph in the slow lane on the interstate, the slow person will bring the average way down. On the other hand, the MEDIAN speed, meaning the speed of the person who has equal numbers of people who are faster than him and slower than him, will be faster than the speed limit.
The strech of I-15 is only 2 lanes each direction. There is often a lot of traffic and it can slow to a crawl. They are also doing construction on that highway to make it more lanes. This will aliviate some of the congestion, but for now it just causes slower speeds. I for one travel about 40 miles a day on I-5 and I generally am going between 50 and 65 depending on if it up hill or down hill. I pay attention to my throttle position and not the speed. The speed limit is 65. I getting 40% higher than the EPA estimates my car should get as a combined city / highway mileage. I am constantly being passed, but the savings are more important than the speed.
the answer is that you must understand the difference between the mean and the median. If 90% of the drivers are driving over the speed limit, but one old person in a Buick is driving EXTREMELY slowly, say 30 mph in the slow lane on the interstate, the slow person will bring the average way down. On the other hand, the MEDIAN speed, meaning the speed of the person who has equal numbers of people who are faster than him and slower than him, will be faster than the speed limit.
Did people suddenly forget what average means? Factor in congestion, egress and ingress alone and suddenly that number would be pushed over the speed limit…
To average the speed limit implies you MUST have EXCEEDED the speed limit to achieve that average.
Common sense people…
Did people suddenly forget what average means? Factor in congestion, egress and ingress alone and suddenly that number would be pushed over the speed limit…
To average the speed limit implies you MUST have EXCEEDED the speed limit to achieve that average.
Common sense people…
I drove I-80 between Nevada and utah in a 26′ Penske truck, towing a car carrying trailer. I noticed that cars were flying by me, but the combination of wind, and the very real fact of just how much more Diesel a truck burns once it goes over 65 made pretty much all the truckers stay right about that speed.
I drove I-80 between Nevada and utah in a 26′ Penske truck, towing a car carrying trailer. I noticed that cars were flying by me, but the combination of wind, and the very real fact of just how much more Diesel a truck burns once it goes over 65 made pretty much all the truckers stay right about that speed.
If you compare your GPS derived speed vs what the speedometer actually says, you’ll notice the Speedometer is not very accurate. In general the higher your speed the further the speedometer is miss-representing the facts. In my Toyota Tacoma 60 indicated is 56 on GPS and 75 indicated is about 69 on GPS. I’ve seen similar effects on Honda Accords and Civics.
I can’t tell if this is intentional by the car companies or not. It does reduce speeding tickets. Messes up drive time calculations.
If you compare your GPS derived speed vs what the speedometer actually says, you’ll notice the Speedometer is not very accurate. In general the higher your speed the further the speedometer is miss-representing the facts. In my Toyota Tacoma 60 indicated is 56 on GPS and 75 indicated is about 69 on GPS. I’ve seen similar effects on Honda Accords and Civics.
I can’t tell if this is intentional by the car companies or not. It does reduce speeding tickets. Messes up drive time calculations.
I don’t think it has to do with the slow driver you get stuck behind, but rather, it probably doesn’t adjusts the speeds when there is road constuction or when there is heavy traffic that’s not moving. If there are people not moving at all, it will quickly lower the average.
I don’t think it has to do with the slow driver you get stuck behind, but rather, it probably doesn’t adjusts the speeds when there is road constuction or when there is heavy traffic that’s not moving. If there are people not moving at all, it will quickly lower the average.
I just finished a 4000 mile trip from Appleton, Wisconsin to Oregon by way of Albuquerque and I found that if I did the speed limit on my motorcycle (usually 70mph) even the semi-trucks would pass me. I had to drive 80mph to avoid being blown away by the trucks’ wind and dust. I found most cars in the west on the highways cruised about 80-85, a few at 90-105mph. So the average speed they measure includes traffic jams in the East, where no one goes more than 2-5mph. Overall, I find that the cars on the highway were way faster than the speed limit, even with speedo errors. This was in Sept 09.
I just finished a 4000 mile trip from Appleton, Wisconsin to Oregon by way of Albuquerque and I found that if I did the speed limit on my motorcycle (usually 70mph) even the semi-trucks would pass me. I had to drive 80mph to avoid being blown away by the trucks’ wind and dust. I found most cars in the west on the highways cruised about 80-85, a few at 90-105mph. So the average speed they measure includes traffic jams in the East, where no one goes more than 2-5mph. Overall, I find that the cars on the highway were way faster than the speed limit, even with speedo errors. This was in Sept 09.
In New Jersey, ten over is pretty much what the traffic pattern (and the State Police) tolerate during daylight
hours when congestion permits. They’re fast here, but they’re generally good drivers on limited access highways.
It would take a significant hike in fuel prices to change that behavior here. And higher fuel taxes would accomplish many other wondrous things like providing revenue for road maintenance, curbing the urge to drive (lowering congestion) and encouraging folks to buy thrifty (smaller, more fun to drive) vehicles.
In New Jersey, ten over is pretty much what the traffic pattern (and the State Police) tolerate during daylight
hours when congestion permits. They’re fast here, but they’re generally good drivers on limited access highways.
It would take a significant hike in fuel prices to change that behavior here. And higher fuel taxes would accomplish many other wondrous things like providing revenue for road maintenance, curbing the urge to drive (lowering congestion) and encouraging folks to buy thrifty (smaller, more fun to drive) vehicles.
For you young whippersnappers who don’t remember studies done before you were born, in the late 70′s the National Highway Administration (please do NOT confuse them with the National Highway Traffic Safety Administration) conducted an analysis of speed limits, compliance and crashes on many roads within the United States.
Their most memorable conclusions were that most speed limits in the United States were set AT or BELOW the minimum safe speed on the roadway. This was determined as the speed at which crashes increased in number compared to higher speeds.
The second memorable conclusion was that the drivers on these roads were better at selecting the safe speed on the road than were the “traffic engineers” who set the speed limits. They attributed this to outside influences, or lobbyists.
They concluded that most drivers in the U.S. drove at a speed where they felt comfortable, and that this comfort zone was always in the range of maximum safety.
As this study was in disagreement with NHTSA’s mantra that “Speed Kills” it got very little publication.
For you young whippersnappers who don’t remember studies done before you were born, in the late 70′s the National Highway Administration (please do NOT confuse them with the National Highway Traffic Safety Administration) conducted an analysis of speed limits, compliance and crashes on many roads within the United States.
Their most memorable conclusions were that most speed limits in the United States were set AT or BELOW the minimum safe speed on the roadway. This was determined as the speed at which crashes increased in number compared to higher speeds.
The second memorable conclusion was that the drivers on these roads were better at selecting the safe speed on the road than were the “traffic engineers” who set the speed limits. They attributed this to outside influences, or lobbyists.
They concluded that most drivers in the U.S. drove at a speed where they felt comfortable, and that this comfort zone was always in the range of maximum safety.
As this study was in disagreement with NHTSA’s mantra that “Speed Kills” it got very little publication.
Herb, your GPS is measuring distance between locations and calculating speed based on the time required, whereas the speedometer is reporting instantaneous speed around curves as well as on a straightaway.
The GPS speed should be very accurate only if you are traveling on a straight and level road.
Try using a stopwatch for several miles of interstate highway using the mile markers. Hold a steady speed. You may just be surprised at the accuracy of modern speedometers. However all bets are OFF if your car is over 15 years old, or if you have changed tire sizes without having the speedometer corrected for the new tire diameter.
Herb, your GPS is measuring distance between locations and calculating speed based on the time required, whereas the speedometer is reporting instantaneous speed around curves as well as on a straightaway.
The GPS speed should be very accurate only if you are traveling on a straight and level road.
Try using a stopwatch for several miles of interstate highway using the mile markers. Hold a steady speed. You may just be surprised at the accuracy of modern speedometers. However all bets are OFF if your car is over 15 years old, or if you have changed tire sizes without having the speedometer corrected for the new tire diameter.
The researchers clearly were not driving the MA Pike during non-rush hours. 65 mph limit @ 75 in the passing lane I would risk physical harm from the road rage masses.
The researchers clearly were not driving the MA Pike during non-rush hours. 65 mph limit @ 75 in the passing lane I would risk physical harm from the road rage masses.
“In my own personal experience, when I drive the speed limit (65 mph here in CT) I get passed by everybody but the little old ladies in their Buicks.”
By definition, everybody who passes you is going faster than you. You can see, as they pass you, every one of them. Do you actually notice how many people are behind you, for miles and miles, who haven’t passed you yet? There’s a whole highway full of people back there. And if any of them were going faster than you, they’d have passed you.
“In my own personal experience, when I drive the speed limit (65 mph here in CT) I get passed by everybody but the little old ladies in their Buicks.”
By definition, everybody who passes you is going faster than you. You can see, as they pass you, every one of them. Do you actually notice how many people are behind you, for miles and miles, who haven’t passed you yet? There’s a whole highway full of people back there. And if any of them were going faster than you, they’d have passed you.