Historically, highway fatalities have comprised about 95 percent of all transportation-related deaths in the United States, and it is on roads and highways where the greatest gains can be made towards reaching the U.S. Department of Transportation’s (USDOT’s) ultimate goal of zero transportation-related deaths. Since Congress established the Department 50 years ago, notable progress in highway safety has been made.

The latest available final data show that, in 2014, 32,675 people died on U.S. highways—more than 18,000 fewer than in 1966, when 50,894 casualties were recorded [1]. Although any death is unacceptable, this drop is notable given that from 1966 to 2014 the U.S. population increased more than 62 percent— from 196.6 to 318.9 million [2], and annual vehicle-miles traveled (vmt) more than tripled—from 926 to 3,026 billion miles. During that time period, the highway fatality rate dropped from 5.5 to 1.1 deaths per 100 million vmt.

1966—A Pivotal Year for Highway Safety

Fifty years ago, on September 9, 1966, in answer to an alarming growth in annual highway-related deaths, President Lyndon Johnson signed both the National Traffic and Motor Vehicle Safety Act and the Highway Safety Act into law [3]. And on October 15, 1966, Congress established the USDOT with a multimodal mission to “Serve the United States by ensuring a fast, safe, efficient, accessible and convenient transportation system ...” [4]. This legislation also established the agency that 4 years later would become the National Highway Traffic Safety Administration (NHTSA).

Although these actions firmly established the Federal Government’s responsibility for setting and enforcing transportation safety standards for all modes of transportation, the greatest impact would be on highway safety.

A Snowball Effect

Since 1966 there has been a dramatic drop in highway deaths. Many factors are responsible for this decrease—both regulatory and social:

• Safer vehicle designs and new safety technologies, such as seat belts, air bags, and electronic stability control, combined with programs to increase the use of seat belts and other safety equipment. NHTSA estimates that these technologies saved more than 600,000 lives from 1960 through 2012—nearly 28,000 in 2012 alone, of which more than half were saved by seat belts [5].
• Safer roads, including major new infrastructure, such as the Interstate Highway System and gradual improvements to existing roads, such as guardrails, lighting, and rumble strips.
• Behavioral safety programs, such as high-visibility enforcement and child occupant protection crusades, have encouraged more people to buckle up, use appropriate child safety seats, and to drive sober.
• More comprehensive and standardized emergency medical services, more effective transport and trauma treatment, and developments in medicine that made injuries more survivable [5].

While it is not possible to pin an exact number of lives saved to a particular safety factor, regulatory or otherwise, it is possible to show the cumulative effect of these innovations over time.

The 1960s

The decade of the 60s would see highway fatalities increase 47.1 percent, from 36,399 deaths in 1960 to 53,543 deaths in 1969. In near parallel, vehicle-miles traveled increased 47.8 percent, from 719 to 1,062 billion miles during that same time period. The number of highway fatalities would continue to increase well into the 1970s, until the effects of new regulations and social reforms finally kicked in.

The 1970s

From 1970 through 1979, nearly a half million lives (498,356) were lost on U.S. roads. In 1972 U.S. highways would claim 54,589 lives—the highest number ever recorded. But as the decade closed, highway deaths per 100 million vmt had dropped from 4.7 in 1970 to 3.3 in 1979, even as vehicle-miles traveled increased by 37.8 percent. Still, the 51,093 lives lost in 1979 nearly matched the 52,627 lost in 1970 [6].

The 1980s

Finally, the decade of the 80s would show a notable drop in highway deaths, with 5,500 fewer lives lost in 1989 than in 1980 (45,582 v. 51,091). Even more remarkable, this drop occurred in the face of a 37.6 percent increase in vehicle-miles traveled and a population that grew by nearly 20 million, pushing down the number of lives lost from 3.4 to 2.2 per 100 million vmt.

The 1990s

At first glance the drop in the annual number of lives lost at the beginning of the decade (44,599) versus those lost at the end of the decade (41,717) might seem unremarkable. But from 1990 through 1999 the U.S. population increased by more than 23 million, while the rate of lives lost on U.S. highways continued to fall, from 2.1 to 1.6 per 100 million vmt—a nearly 72 percent drop from the 5.5 deaths per 100 million vmt recorded in 1966.

A New Century

The first years of the 21st century saw the highway fatality rate per 100 million vmt drop nearly 30 percent, falling from 1.5 deaths per 100 million vmt in 2000 to 1.1 by 2014 [7]. By 2004 the .08 blood alcohol limit and the “Click It or Ticket” campaign were enforced nationwide. Distracted driving emerged as a new challenge, and intelligent transportation systems, electronic stability controls, and the advent of self-driving cars ushered in a new era of innovations designed to mitigate the effects of human error.

Getting to Zero

A number of active safety systems are now available or are under development: forward collision warning, active braking, rear-view backup cameras, parking assist, lane departure, and blind spot warning—all technologies aimed at reducing or eliminating the effects of human error. In addition to these systems, connected and automated vehicle technologies are poised to play prominent roles in further reducing highway fatalities.

References

[1] U.S. Department of Transportation, National Highway Traffic Safety Administration, press release, Traffic Fatalities Fall in 2014, but Early Estimates Show 2015 Trending Higher, Nov. 24, 2015, www.nhtsa.gov as of May 25, 2016.

[2] U.S. Department of Commerce, Bureau of the Census, Population Estimates, www.census.gov as of May 25, 2016.

[3] U.S. Congress, Library of Congress, 112th Congress Senate Report 112-083, http://thomas.loc.gov as of May 25, 2016.

[4] U.S. Department of Transportation, mission statement, www.transportation.gov as of May 25, 2016.

[5] U.S. Department of Transportation, National Highway Traffic Safety Administration, Lives Saved by Vehicle Safety Technologies and Associated Federal Motor Vehicle Safety Standards, 1960 to 2012, January 2015, www.its.dot.gov as of May 25, 2016.

[6] U.S. Department of Transportation, National Highway Traffic Safety Administration, Office of Highway Policy Information, Highway Statistics Series, www.fhwa.dot.gov as of May 25, 2016.

[7] U.S. Department of Transportation, National Highway Traffic Safety Administration, Traffic Safety Facts 2014, www-nrd.nhtsa.dot.gov as of May 25, 2016.