The incidence of alcohol-impaired driving has been reduced but remains a major problem. NHTSA and the Institute undertook a national roadside breath survey in 1996, patterned after 1986 and 1973 surveys, and found that 83 percent of drivers had no measurable alcohol, a significant increase in nondrinking drivers above the rates of 74 percent in 1986 and 64 percent in 1973.10 In 1996, 7.7 percent of drivers had BACs at or above 0.05 percent, compared with 8.4 percent in 1986 and 13.7 percent in 1973. The proportion of drivers with BACs at or above 0.10 percent was 2.8 percent in 1996, 3.2 percent in 1986, and 5 percent in 1973.