Older Drivers Driving Older Cars
A snapshot analysis of the National Household Travel Survey 2001

The aging of the driving population in the US has raised many safety concerns, particularly focused on elderly driver’s declining vision and ability.  The coming population bubble of drivers entering their golden years is important to understand for both policy and safety considerations. 

Analysis of the 2001 NHTS shows that older drivers in the U.S. drive older cars than younger drivers.  Insurance companies have indicated that the very young and the very old are statistically the populations more at risk in travel—a greater likelihood of being involved in an accident and a greater likelihood of injuries when accidents occur.  The introduction of safety equipment into the U.S. fleet may have a time-delay in helping keep older drivers safe.

The analysis of fleet composition and age of the fleet in conjunction with the demographics of the main driver of each household vehicle shows that older drivers may be driving older, less safety-equipped vehicles.  First, a quick history of safety equipment:

• 1955 Volvo offers seat belts as standard equipment.

• 1956 Ford offers seat belts as an option (first U.S. manufacturer). 
• 1968 NHTSA requires lap or lap and shoulder belts for front and rear seats in passenger cars.
• 1972 NHTSA requires lap or lap and shoulder belts for front and rear seats in multi-purpose passenger vehicles and trucks
• Starting with 1987 model year NHSTA requires either automatic seatbelts or driver-side airbags in passenger vehicles (cars and trucks).
• 1998 model year passenger vehicles are required to have passenger-side airbags.
• Mandatory seatbelt usage laws gained popularity in the 1990’s and now every State but New Hampshire has one.

The age of the vehicle may indicate the types of safety features available.  For example, pre-1988 vehicles may not have automatic seatbelts, and 26 percent of drivers over the age of 80 are driving pre-1988 vehicles, compared to 16 percent of drivers under 60. Pre-1998 vehicles may not have passenger side airbags, and 85 percent of drivers over 80 are in pre-1998 vehicles. Women are more likely than men to keep aging vehicles as they get older, or to drive newer vehicles when younger.

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Most of the vehicles driven by older drivers will have at least a seatbelt available for use, but do older drivers use seatbelts?  The 1995 NPTS asked a number of scenarios where a seatbelt might not be used (“When forgotten”, “When on just a short trip”, etc.). The good news is that older drivers are slightly more likely than drivers aged 15 – 65 to wear a seatbelt.  The bad news is that nearly one out of five older drivers sometime do not wear a seatbelt.  (The 2001 NHTS did not include this question).

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Crash rates are an important tool in targeting safety measures, programs and campaigns.  Of course, calculating a crash rate by age requires a survey that collects vehicle miles for all purposes by age group, like the NHTS.

A crash rate is computed to show highway accidents or fatalities per 100 million vehicle miles of travel (VMT).  Crash rates are often computed by age of the driver, and based on the number of crashes per 100 million VMT. The importance of calculating the crash rate this way is that it puts accidents and fatalities into the context of the amount of driving done. Thus it shows a very different picture from the distribution of licensed drivers or of fatal accidents.  Once the crash rate is calculated, it is obvious that the risk of fatality increases for the elderly.

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