Projecting Fatalities in Crashes Involving Older Drivers, 2000-2025

seatbelt use variable was invariant across gender. There is no smooth pattern of increase or
decrease in the contribution of either variable as we move up the age groups. Among men,
seatbelt use contributes the most among the 70-74 and 85+ groups, 60% to 63%, and the
least to decreases in driver crash risk among 65-69, 75-79, and 80-84 year olds, from 40%
to 42%. Growth in seatbelt use contributes the most to decreases in women’s driver crash
risk among the 65-69 year olds, around 37%, the least among the 80-84 group, and at an
intermediate level among the 70-74 and 75-79 year olds, at 55% and 49%.
Table 8.3. The Determinants of Projected Changes in Driver Risk, National Level
Men Women
Age Income Seatbelt Income Seatbelt
65-69 58.09% 41.94% 62.46% 37.44%
70-74 39.92% 59.90% 44.13% 55.78%
75-79 57.71% 42.19% 50.54% 49.37%
80-84 59.19% 40.68% 62.40% 37.40%
85+ 37.17% 62.93% 38.69% 61.42%
While seatbelt use is a traditional focus of concern, the substantial contribution of
income growth to decreasing crash risk in these projections is important as 40% to 60% of
the decrease in this risk indicator is attributable to increasing income. Our modeling has not
specified the routes of effect of higher real, elderly income, but we have pointed to the most
likely possibilities as ability to afford safer equipment and generally higher valuation of safety
which may spill over into driving practices as well as equipment purchases. Income and
health are generally positively correlated, although in the regressions underlying these
projections, better health, as measured by our indicator, would have elevated crash rates. The
health-income-crash rate relationship needs further research.
Regional variations in the different variables’ contributions to the crash rate decline
are not as striking as they have been in some of the other projections, as Table 8.4 clearly
shows. The seatbelt contribution to crash rate decline is largest among western women 85+,
at 83% (followed by western men in the same age group, at 74%), and the lowest is among
GM Project G.6 8 - 14
October 2000