What IF.....55MPH was the speed limit

People often like to lie with statistics lets look at some. NAS and other groups peg the gas savings around 0.5%. This is smaller than a number of easy measures would have lowered gas consumption.

What about death rates?

In 1973 before the law there 54,052 deaths and a rate of 4.116
In 1986 the last year all roads had a maximum of 55 there were 46,087 deaths and a rate of 2.512

The number of deaths dropped substantially as did the death rate. But was this all due to the speed limit decrease? Let's look further

In 1995 when the law was repealed there were 41,817 or a death rate of 1.726
That's right the number of deaths and death rate continued to fall with the experiment with higher speed limits. That is why it was removed, with the idea that death rates would continue to fall with safety improvements even without the speed limit. Who was right? Those that attributed the death rate to the speed limit, or those that said removing the 55 mph speed limit would not greatly affect death rates. We have years of statistics

In 2009 there were 33,808 fatalities and a death rate of 1.1/100 million miles.

Between 1973 and 1986 there was a drop of 15.7% during full 55 mph law.
Between 1995 and 2008 (same number of years) there was a drop of 10.5%, if we include 2009 its 19.2%. There was some really low hanging fruit when it came to safety in 1973.

It is difficult to justify any statistical significance to a 55 mph saving lives. The drop from repealing the law is greater than the drop during the law including changing the law. Further the number of deaths on the roads greater than 55 mph are extremely low per vmt. The studies that estimated fatalities would greatly rise, did not consider that fact that higher speed limits on the safest roads, move traffic from less safe roads. You need to analyse changes as a whole.

 

I have to say given the information the steps are probably good

Road repairs, greater enforcement, lower speed limits on the dangerous roads. I wonder though if the trooper driving Corzine's SUV would have been ticketed in New Jersey given the partial cover up. 91 in a 65 is 26mph over the limit, which is reckless in many states. Once roads are improved and accidents drop, perhaps they will raise the speed limit back up to 65

 

A remarkable sight!! Four cars loaded with college students hold traffic to the speed limit on I-285 for 30 solid minutes!!



The New Civil Disobedience: Obeying the Speed Limit « Dvorak News Blog

 

Sounds passive-aggressive to me. No wonder Prius drivers get bad rep.

 

That article was from 2008. I drove through that section Saturday, and nothing's done. I do 65 in the right lane and I'm constantly being passed like I'm standing still. The only thing that was done was that we voted the crook out of office.

 

Someone older told me about DOT trucks blocking lines and going 55MPH to enforce the speed limit in 70's. True?

 

In NJ, we didn't have anyone slowing us down during that period. The traffic jams took care of that.

 

Thanks for the update. Never trust that politician. I take it they didn't do the road improvements either, just dropped the speed limit?

 

Every year automobiles get safer/better built and roads improved. If the figures include all motor vehicles, then helmet laws and the number of states requiring them will have a large effect too.

 

Best study I have seen for a direct comparison of accident rates vs. speed was the speed camera demonstration study done in Scottsdale, AZ in 2006. It included comparisons for the same stretch of highway before cameras, after cameras, and after the cameras were turned back off and included comparison to data from the same time period for other sections of the same freeway with historically similar speeds and trends in accident rates. This was all done over a short enough time period to reduce if not eliminate the affects of other long term trends.

The speed data from before and during the test shows a reduction in mean speed from 73 to 64 mph, and a reduction in standard deviation from 3.5 to 1.2 for the posted 65mph zone. The latter is significant as previous studies have indicated that variation in speed may be more significant to accident rates than absolute speed. Once the equipment was up, detection frequency data was also available for # hits per day on vehicles traveling >76 mph. This is interesting because it includes the test period, but also the deactivation period when the cameras were bagged and it was widely publicized that the test was over, as well as the reactivation period when the cameras came back online. The average frequency of detection was 130 hits/day during the program period, 1482 hits per day during the deactivation period, and 137 hits/day during the reactivation period. So the cameras slowed overall average speed, but also reduced the variation of speed including number of "outliers" traveling >10mph over the posted limit.

During the test period in the test zone, the accident rate (#/year/mile) dropped from 80 in 2005 to 55 in 2006. In the comparison zone for the same period the rate increased from 120 in 2005 to 140 in 2006. Overall the before/during accident rate relative to the comparison zone dropped 53%. Interestingly, the date also showed that the increase in mean travel times for the test zone was more than compensated for by the reduction in accidents, resulting in quicker mean travel times during the test period.

Not long after this study, speed cameras were deployed on a number of AZ freeways. Similar reduction in speeding and accident rates were observed as well as a reduction in fatalities, but I am not aware of any detailed study just raw statistics which can of course be misleading. A few years later the governor instructed the DOT to remove the cameras, despite their demonstrated benefits, because there was a "perception of unfairness".

 

The only people who slow me down on the freeways are people who cant see over the steering wheel, or the ones talking on the cell phone. Now other wise I drive the "basic speed law" As fast as it is safe.

 

I thought the purpose of the cameras was to make money, but the revenue fell short, that is why they pulled them.

http://www.nytimes.com/2010/01/03/us/03arizona.html?_r=1

700,000 cars caught doing over 11 over the limit, while it was well publicized. That does not seem like the cameras were effective in slowing down drivers or generating revenue.
Arizona speed cameras incite a mini revolt - Los Angeles Times

Yep even less money. Why do you think Arizona put the cameras in, to make money and spy on the citizens. It was alleged that many of these cameras went up where the speed limit temporarily dropped to 55 then went back to 65. That might explain the amount of citizen anger at redflex and the state, as well as the high numbers ignoring the tickets.

Let's look at what Arizona is doing wrong -
Arizona road deaths increase
Fatalities went up in 2011 after declining in 2010, they removed the cameras in 2010, and we should of seen the uptick there if it really was the cameras

Read more: http://www.azcentral.com/news/articles/2012/08/16/20120816arizona-road-deaths-increase.html#ixzz24mhsoXKk
Why did the deaths go up, instead of down as they did in the rest of the country?

Maybe we actually need distracted driving laws, and cops instead of cameras to enforce speeding.

 

I can't believe they didn't hang him for MF Global. Anyway, no improvements. The section that the speed limit dropped on is 3 and 4 lanes across on each side. What they did do was widen the Parkway from 2 to 3 lanes on each side on the section below that part, and it's always been 65 there.

And it just gets better.
N.J. Police Suspended Over Caravan - WSJ.com

 

Wasn't particularly trying to start a debate on speed cameras. Just citing an interesting study that provided a rare opportunity to compare directly the relation of vehicle speed and accident rates.

 

Absolutely agree. Roads are safer if vehicles are going bellow the speed that the road is designed for, and the cars are going at a more uniform speed. If there are differences in speed, and the roads are under capacity, they still can be safe with educated drivers, not tailgating, and slower traffic to the right

The number of tickets on those arizona roads, of cars going over 11+ mph above the speed limit were indicating the need to educate the public and at the same time put more cars on the road to enforce the law. The state of Arizona has done the opposite. Those traffic cameras were all about revenue not public safety though. That doesn't mean that states can not use cameras to increase public safety, but Arizona did it in the wrong way.

 

I think that's more or less our state motto, isn't it

Rob

 

FWIW I agree the revenue projection was used too much to help sell it, but I'm not convinced that was the actual purpose though. Its also worth noting that in large part due to the terms of the contract under which they were set up, the state was still making money on them even with the lower than expected revenue. The company that operated them assumed much of the profit risk. So canceling the contract actually lost the state money in the midst of a large budget shortfall which included large cuts to police enforcement and other services.

The Department of Public Safety report on the cameras showed the total number of detections per month across all sites falling from a little over 200,000 in the first months, to <100,000 by the end of the first year. At two particular sites right in downtown Phoenix (coincidentally on my commute) detections fell from 21-23,000 per month per camera to ~2500 by the end of the first year. So 700,000 violations is still a lot, but significantly less than might have been expected without the cameras. One could argue their effectiveness at curbing speeding was a key factor in the revenue shortfall, which was pointed out in the state audit report. DPS again credited the cameras with controlling speed far more effectively than they could with officers even without the budget cuts, and at a much lower cost. As you say traffic fatalities fell while the cameras were in use, and increased after they were shut off, which I'd say is another indicator they were pretty effective at increasing saftey.

Again, don't really want to start a debate on speed cameras, but just pointing out that given the highly politicized atmosphere that developed around the issue its pretty tough to find unbiased accounts of what did and didn't happen.

 

Its good to doubt that. The purpose was government control of the public.bwhahahahaha

This is moldy and was done before the widespread Arizona trial
http://tti.tamu.edu/documents/TTI-2006-4.pdf
It talks about the effectiveness, but also the trouble with poorly implemented programs. Specifically it talks about programs failing because the public believes they are for revenue enhancement. They also note that speed cameras can not be used instead of human enforcement. Certainly lessons some in arizona have now learned.

This is from the conclusion