Women Drivers: Hidden Health Risk To Men

Women drive only 30% of miles driven but are in 37% of the fatal accidents

Scientific Evidence that Men and Women are Designed Differently

How drunk does a man have to be to drive as dangerously as a sober woman?

Answer:  seven drinks

Clues that NHTSA is too much of an advocacy organization to trust their conclusions

There are several key pieces of data missing from the NHTSA web site which make it difficult but not impossible to calculate accident rates by race and sex, while the site is flooded with erroneous (and intentionally misleading) information about the adverse effects of drinking and driving.  The data which is suspiciously absent from this voluminous data base is:

The sparse data available from NHTSA would lead one to believe that women drove 30% of the1.5 trillion miles traveled by passenger cars and were 37.1% of the 53,237 drivers involved in accidents resulting in 41,967 traffic fatalities in 1999.  This means that NHTSA believes (and expects us to believe) that, per mile driven, women are only 37% more likely than men to be involved in a fatal accident.  Such a theory is simply not consistent with other observations, like those above, and we hereby challenge NHTSA to produce the actual facts.

Additionally, countries like Sweden, England, and Ireland where there are no blacks on the road, and where drivers license testing prevents them from driving in those countries, consistently have motor vehicle fatality rates less than ONE THIRD of ours.  What this means that, in addition to women drivers being such a health risk for men, American blacks are directly responsible for an ADDITIONAL 30,000 American lives lost on the road EVERY YEAR.

The above is the conclusion you might have reached had you queried the FARS data base on October 30, 2000 which showed that women drivers were involved in only 37% of fatal accidents.  But if you take a close look by vehicle type, you will see that women were 15,181 or 43% of the 35,510 drivers of passenger cars:

In other words, because the 1.5 trillion vehicle miles driven is for passenger cars only, we must compare that only to accidents involving passenger cars.  The following more accurate table shows that women drivers are 73% more likely to have a fatal accident than men drivers, rather than only 37%.

Ocbober 30, 2000

1999 Annual Report File

However, there are a number of reasons to be suspicious of NHTSA's claim that women drive 30% of VMT (vehicle miles of travel):

1. It would require us to believe that women are only 70% more likely than men to have accident when driving a passenger car but six times more likely when driving a truck.
2. It would require us to believe that men truckers have a higher accident rate than women drivers of passenger cars (85.6 vs. 33.3 accidents per billion miles).
3. While not broken down by sex, Table No 1093 of the 2003 Statistical Abstract of the United States suggests that women drive only 14.3% of VMT.

It's hard to imagine that women who drive trucks are six times more likely to have a fatal accident than men who drive trucks, but that women who drive passenger cars are only 70% more likely than men who drive passenger cars.   Or that women who drive passenger cars are less likely than men who drive trucks to have a fatal accident.  It would be expected that women who drive passenger cars would have an accident rate higher than men which is equivalent to the amount by which women truckers have more accidents than men truckers, or 6X.

ULTRA-CONSERVATIVE CALCULATION

Even accepting the NHTSA data at face value, the higher probability that women will have an automobile accident contributes to an increase in the accident rate for men.  The calculations for the most conservative figure of 35% are shown below to enable a comparison to be made to the results of the 56% figure.  To determine exactly how much higher the accident rate for men is because of women drivers it is necessary to calculate the rate per one million miles that both men and women are expected to have an accident.  If we let N_m be the number of accidents per million miles that a man is expected have a single driver auto accident, and N_f that a woman will, then we have two equations and two variables.  The total number of accidents per million miles that a man is expected to have an accident, R_m, is the sum of his likelihood per million miles of having a single driver accident N_m, the square of this probability to represent a two driver accident involving another man N_m², and N_m  times N_f  to represent a two driver accident involving a woman.  For simplicity, accidents involving more than two drivers are omitted, but they are rare enough that the ratios below won't change significantly and it is unlikely that the probability of either sex to have a multiple car crash is much different than the probability of a two driver crash:

(N_m +  .65N_m²  +.35 N_mN_f) x 965 billion miles driven = 2,418,799 accidents

R_m = N_m +  .65N_m²  + .35N_mN_f = 2.5

The equation for women is similar:

(N_f +  .35N_f²  + .65N_mN_f) x 513 billion miles driven = 1,701,043 accidents

R_f = N_f +  N_f²  + N_mN_f = 3.3

N_f = (2.5 - N_m - .65N_m²)/.35N_m

(2.5 - N_m - .65N_m²)/.35N_m + 2.857(6.25 -5N_m - 2.25N_m² + 1.3N_m³ + .4225N_m⁴ )/N_m² + 1.857(2.5 -N_m - .65N_m²) = 3.3    

1.155N_m²  = 2.5N_m - N_m² - .65N_m³ + 6.25 - 5N_m - 2.25N_m² + 1.3N_m³ + .4225N_m⁴ + 1.6429N_m^{2 -} .65N_m^{3 -} .4225N_m⁴

2.7621N_m²  + 2.5N_m   = 6.25

N_m = 1.11829 = The number of single driver accidents per million miles that that a man is expected to have.

N_f = 1.4533 = The number of single driver accidents per million miles that that a woman is expected to have.

N_f = 1.3 x N_m

If all drivers were men who drove the 1,478 billion miles which are currently driven by both men and women, the total accident rate would be 2.37 accidents per million miles, for a total of 3,497,018 drivers in accidents:

(N_m + N_m²) x 1,478,000 million miles = 3,501,179 drivers in accidents.

If all drivers were women who drove the 1,478 billion miles which are currently driven by both men and women, the total accident rate would be 3.67 accidents per million miles, for a total of  5,417,947 drivers in accidents:

(N_f + N_f²) x 1,478,000 million miles =  5,269,840 drivers in accidents.

With the assumption that women drive 35% of all miles, if only men drove today, the number of drivers in accidents would decrease from 4,119,842 to 3,501,179 per year, a reduction of 16.9%.  If only women drove, the number of drivers in accidents would increase from 3,497,018 to 5,269,840 per year, a 28.7% increase and there would be 50% more accidents than if only men drove.  Women who have accidents with men increase men's overall accident rate per million miles from 2.37 to 2.51, a 5.5% increase.

At current traffic fatality rates, the average man who drives 15,000 miles per year for fifty years has a 1.91% probability of dying in a traffic crash.  But a non-drinking woman driving the same distance has a 5.63% probability of dying in a traffic crash, almost three times as high.  Because men are safer drivers per mile driven, if only men drove all of the miles currently driven by both men and women, his probability would decrease to 1.59%, which would save a quarter of a million lives over the next three decades.  Contrary to popular belief, the NHTSA data shows that the drinking man driver has a better traffic safety record than the non-drinking man driver, with a probability over 50 years of only 0.82%.  If only drinking men drove all the miles currently driven by both men and women, almost a million lives would be saved over the next 3 decades, compared to only 157,000 lives which would be expected to be saved by the use of seat belts over that time.

Conversely, if only women drove those same miles in that same timeframe, there would be almost half a million additional traffic fatalities.

The results of the National Personal Transportation Survey, which are in a pdf file located at http://www.fhwa.dot.gov/ohim/1983/vol1pt1.pdf show that women drive only 30% of all miles, and men drive 70%, which changes the ratios considerably.  This would mean that women are 56% more likely per mile than men to have an accident rather than only 33%.  This means that if only men drove that there would be 2.22 accidents per million miles, which is 21.8% lower than the current rate of 2.84 crashes per million miles, which would save 9,159 lives per year.  This is also 8.3% lower than men's current crash rate of 2.42, which means that 8.3% or 200,760 of the accidents which men currently have are caused by women drivers.  If only women drove, the accident rate would be 4.46 accidents per million miles, which is 57% higher than the current total crash rate and 18% higher than women's current crash rate of 3.78, which would increase the number of traffic fatalities by 23,893 per year.  Over the next thirty years, based on the current population growth projection of 1.1% per year, there would be 336,000 fewer traffic fatalities if only men drove.  Conversely, there would be 877,000 more traffic fatalities if only women drove.

This data shows that if only men drove, the cost to repair automobile crashes would be between $30 billion to $44  billion less, and 9,159 of the 41,967 lives currently lost each year to auto accidents would be saved.  Over the next three decades, this is a savings of as much as $1.6 trillion and 336,000 lives.

If you were to believe all of the claims made by the NHTSA (National Highway Traffic Safety Administration) Report DOT HS 808 770, you would believe that all kinds of new laws (DUI Laws, Helmet Laws, Safety Laws, Minimum Age Drinking Laws, Open Container Laws, Repeat Intoxicated Driver Laws, Bicycle Helmet Laws, Air Bag Laws, Child Passenger Laws, etc) saved 21,880 lives in one year.  However, the actual decrease in the number of fatalities due to the decrease in the motor vehicle fatality rate was only 4,423, which is 17,457 fewer than all the claims.  It is suspicious that NHTSA claims that the percent of alcohol-related fatalities decreased from 51% in 1987 to 30.3% in 1997, when such a decrease is almost equal to the actual total decrease in traffic fatalities.   It is also contradictory to police reports in the Statistical Abstract of the United States which report that only 4% of all accidents are "alcohol involved".

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