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This is actually the older of the two articles, but I was more excited about the mapping  for part 1.

I wanted to prove to myself that traffic was getting safer over the years, and that transit was even safer than that. So I hunted for all the dta I could find from sites run by the FHWA, FTA, DOT, BTS, and APTA.  I’ll provide link at the end of this.

I found some very long run data, which showed that the death toll from traffic has far exceeded the death toll form our wars , with a constant pile of stilled souls behind their wheels, on the curbs, and in the ditches.  On the other hand, we’ve been driving a lot more.  Cumulatively, Americans drive half the speed of light every year (half a light year, in one year).  To host all that dirving, We’ve built over half of our 4.5 million miles of roads in the 20th century, and paved almost all of it

Numbers

It is an easy matter to divide these things to obtain the probability of dying in traffic.  By the measure of mile traveled or even trips traveled, it has gotten a lot safer.  The safety effect of building more roads is at best equivocal.  We build roads to address congestion, not safety.  And the faster people can go, the more of a problem it becomes when they hit something.

RateDeaths

So, until very recently, the more roads we built, the more we died in traffic.  The relationship was nearly direct between 1994 and 2004.  Despite the recent drop in fatalities, it hasn’t gotten significantly better that it was during road rationing during WW2.  Ask your state highway engineers about this when they propose new routes and bypasses in your area.

In looking at the data last week, I noticed the number of fatal collisions wasn’t much different between 2006 and 2012.  Was the number of collisions staying constant while the number of death fell?

CollsFatals

Nope.

What was the chance of dying if you were a driver versus a passenger.  The average occupancy of cars is 1.6 peopl, so I’d expect this to be 10 drivers for every six passengers.  Its actually a little lower than this.

ProbDeathColl

It looks like its getting safer for passengers, a little safer for drivers and a lot less safer for “others”.  The natural tendency is to assume that this means bikers and walkers, but in fact they are genreally safer than ever.

DeathsMode

The problem with this is that I can’t give a good rate over time for biking and walking, as no one is taking a nationwide survey of how much we bike and walk.  Biking and walking are scrunched up on the bottom of the scale here, so I wanted to expand it with the real victim in the “other” category: motorcyclists

DeathsMode2

By the way, in case you think transit is a poor alternative, below is the per passenger mile fatality rate for bus, rail transit, and traffic vehicle occupants.  If I included those killed by traffic outside the car, the fatality rates for traffic would be even higher.

ProbDeathTrans

http://www-fars.nhtsa.dot.gov/Main/index.aspx

http://www.iihs.org/research/fatality.aspx?topicName=Pedestrians&year=2010

http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_02_01.html

http://www.fhwa.dot.gov/ohim/summary95/section2.html

http://www.rita.dot.gov/bts/sites/rita.dot.gov.bts/files/publications/national_transportation_statistics/html/table_01_04.html

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