The ups and downs of cycling casualties
Mon, August 10, 2009 
I came across this graph that compares cycling and pedestrian deaths in the US during the period from 1986 to the year 2000.
Over the period pedestrian deaths (Shown in pink.) declined at a fairly steady and consistent rate. I’m not sure the reason; after all motor vehicle traffic has increased and driving standards have certainly decreased over this period.
Does more cars mean less pedestrians, or maybe more cars and the congestion it brings to our cities mean slower traffic, resulting in less pedestrian casualties. Because speed definitely kills those of us unprotected by a steel cage, especially when hit by same steel cage. Or could be pedestrians are just getting street smart.
What I found interesting was the same downward trend for cyclists, but far from being a steady decline it was up and down. Given that there are far more pedestrians than cyclists the chart shows the rate of decline for the two groups.
Starting at the same place in 1986; it showed cycling casualties slightly above the rate of decline for pedestrians at the end of the period.
The article accompanying the chart is about helmet use, and points out that although helmet use went from near zero to 30% in the period, the decline in cycling deaths failed to stay with the decline in pedestrian fatalities. The article doesn’t mention that pedestrian helmet use is still zero.
What immediately struck me was the sharp decline in cycling deaths in 1992; I remember the date well. It was the period when my business went right down the toilet. The reason the quite sudden rise in popularity of the Off Road Mountain Bike, and the accompanying drop in demand for road bikes.
Bicycle dealers nationwide, some almost overnight stopped selling road bikes and switched over exclusively to selling MTBs. It is no wonder cycling deaths dropped so dramatically, cyclists in the US abandoned the roads for dirt trails.
The sharp decline in casualties in 1992 was followed by a dramatic increase in the next five years before moving once again on a steady decline.
My thoughts on this sudden increase; less cyclists on the roads meant that the few diehard roadies left out there were at greater risk for being hit. Out of sight, out of mind as far as the average American driver was concerned, and the motorist doesn't think of cyclists until the moment of impact.
The increase in numbers of cycling deaths in the mid 1990s was even more dramatic when you consider that there were still less people riding on the roads.
I also believe, giving up the roads in the early 1990s also lead to all this hostility towards cyclist. I rode my bike in the US trough the 1980s and agreed there was less traffic, but I never encountered the hostility from drivers there is today.
I quit riding a bike in 1993 when my bike business finally went under, took up running and other forms of exercise, and didn’t start riding again until 2005. It appears this was a good period for me to be off my bike, and off the road.
This more recent article has a chart that goes from 1975 until today. (Shown above.) Interestingly, it shows the sharp decline in 1992, followed by the rise and it would take another ten years before the figures fell below the 1992 level, followed by a sharp increase.
Why this increase? What are your views? Is it because of the increased hostility and poorer driving habits from other road users? Or is it an increase in bicycle riding meaning there are more inexperienced riders on the road?
In conclusion, to get these casualties into perspective; in 2007 there were a total of 41,059 road deaths in the US, according to this article. Pedestrian fatalities showed the same steady decline, down to 4,654, and the number of cyclists killed in 2007 was 698.
This is less than the low point of 723 in 1992, and about the same as the 690 in the year 2000. I haven’t been able to find an accurate count of the number of regular cyclists in the US, but this article suggests that 3.2 million people ride to work at least one day a week. Does anyone have a more accurate count?
My feelings are, helmets may saves lives, but what really saves lives is defensive riding, plus more cyclists on the road leading to more awareness among drivers that there may be cyclists on the road.
Reader Comments (10)
About the rise in cyclist deaths in 2005: Could it be because gas prices went up very significantly in a matter of a few months at that period? Prices at the beginning of 2005 were around $1.97 and then rose to a little more than $3.00 by September. That may have got more new cyclists on the road.
Another possibility: Lance Armstrong was going for his 7th TDF win that year. That was big news at the time, and it probably got a whole load of people into cycling.
I think that driver hostility and skill (or lack thereof) is mostly constant over time, but more cyclists on the road without the requisite training could be what leads to the greater number of deaths.
It would be interesting to see a plot of cell phone use/texting as a function of accidents in general.
Yohann stole my thunder a bit there, but I'm thinking that if you looked at that graph for 1999 (Lance's first win), you can see a spike and while there was a downward trend for a bit, it seemed to spike again 2003 when Lance was riding for his 5th straight victory (and tying a record for wins in the Tour). If my memory serves me right, I believe there was a spike also when Lemond won his Tours. I certanily know that bicycle sales rose accordingly in the States because of those two riders. Trek was not displeased!!
I'd be surprised if we didn't see huge spikes for the past year and upcoming year simply because of rising gas prices, as Yohann stated above. I know in the SF area, bicycle sales seemed to spike a bit based on fuel costs, but also, the repair side of the business seems to have grown also, meaning older bikes are being brought in for tune ups as they are now being riden again.
Great article, Dave. I think Yohann's points are all good. I would also like to see the rate of cell phone/texting as it relates to these data.
In 2001, texting was opened up for use between competing carriers. It took a couple of years perhaps to catch on as an epidemic (spike up). Then laws slowly are coming onto the books (spike down), and finally drivers realize that the laws are not enforced with any regularity (spike back up).
All I know is that four-way stop signs are no longer the places of civil negotiation they once were. I'm sometimes lucky to get even a look from drivers now. Sometimes they look, but it's that vacant stare as if they are looking through me. Those are the drivers with the bluetooth Robocop appendage.
I also wonder about the rate of pedestrians. Maybe less ped fatalities because there aren't as many peds.
Actually, you're asking the wrong question. If you crunch the numbers, you'll see that the increase after 1993 returns the value to more-or-less the long-term trend; both 1993 and 1994 were less than .05 standard deviations off of the predicted trend from a univariate regression. 1992, though, was nearly two standard deviations below the trend. The same is true of 2003 2005 and 2006 were well above (about 1.6 standard deviations) average, but probably aren't so far above average that, as a social scientist, I'd say that it wasn't just random fluctuations. So the real question is why 1992 and 2003 were exceptionally low, not why the increase in 1993 and 2004.
I think the general decline is due to people wearing helmets more often when they ride. Cycling is kind of looked upon as an "extreme" sport and what better to symbolize that than by wearing a helmet? Before being seen as an "extreme" sport, people would casually ride their bike without a helmet thinking that nothing could happen to them. It's too innocent of an activity.. until they get creamed by a car. Also, I wonder what the average age of a rider is now compared to 10 years ago? With the decline of newspaper routes and kids wanting to work other jobs, how many less kids ride today? Maybe more adults are riding instead and they may tend to be more responsible. I think there are a lot of factors that we just don't know about.
I have heard the statistic that 99.9% of all fatalities with motor vehicles hitting cyclists involved an impaired driver--I believe this comes from Mothers Against Drunk Drivers. That has been the case here in Tucson, AZ where the drivers were either three-sheets-to-the-wind, stoned or both. It also appears that these drivers had many DUI arrests, so it was only a matter of time before they killed a pedestrian or bicyclist. Tucson has great weather, a lot of bike commuters, and tons of roadies--so when those types of drivers get on the roads the chances of them meeting up with us is much higher.
"My feelings are, helmets may saves lives, but what really saves lives is defensive riding, plus more cyclists on the road leading to more awareness among drivers that there may be cyclists on the road."
This would work if you're assuming that motorists are driving safely. In short, your statement is too simplistic. Life would be great if this were the case.
Strictly speaking with regards to 'survivability', whether there is numbers of cyclists on the road or not is not too much a concern when you're hit because whether you survive or not depends on how fast the vehicle was travelling, bicycle orientation wrt to car, impact angle, impact location, how severe your injuries are (especially to the head) and what your age and tolerance limit to these injuries are. I always wonder why studies leave out considering the age, height, weight and anthropometric data of the victims. It is not rocket science to understand that an ageing cyclist pushing 50 or 60 years old does not have the same amount of muscles, bone density or vigor as he had 20-30 years in his prime. It has been well established that tolerance to human injury does depend on age. It has also been known that smaller cyclists gain much higher accelerations when impacted than heavier cyclists.So I say, better count on your lucky stars when you're old, frail and involved in an accident.
For both pedestrians and cyclists, the most frequently injured body part is the head, which is why you should protect it. Cyclists generally impact the car higher than pedestrians because of their higher seating positions. Accidents and their outcomes aren't planned. So why wouldn't one wear a helmet?
In response to your post:
When a bicyclist or pedestrian is run over and killed by a motor vehicle, it is a motor vehicle death; not a pedestrian or cycling death. Unfortunately, we worship the automobile in the western world and we are loath to face up to the fact that their overuse and careless use degrades the environment and the human experience.
I completely agree with you, Dave, that more bicycle riders make the roads safer because we do remind drivers that we are there.
In response to two replies:
Bicycle riding is not an extreme sport. It is natural for a person to casually grab a bicycle and go someplace. People hurtling around in 6,000 pound SUVs is an extreme activity and very few of the people who do it have any idea of the danger they are to themselves and to others.
Bicycle helmets are designed to ameliorate head trauma from a six foot fall to a flat surface or a four foot fall to a curb. The testing agencies explain helmet testing on their websites. They are not designed to protect a person hit by a motor vehicle.
Head injury is well down the list of reasons bicyclists and pedestrians go to the emergency room and serious head trauma is even further down the list. Serious head injury accounts for about 6% bicyclist ER visits.
Bicycle riders and organizations who tout the dangers of cycling do us all a disservice. It is much more dangerous to stay home and watch TV than it is to get some exercise by walking or riding a bicycle.
driving while using a cell phone