Did anyone actually slow down to 55 MPH in 1974?
It was just a giant political show at the time. OMR is right that it was driven more by the insurance companies than fuel savings.
Pulled this from Wiki that sums it up pretty well...
The
National Maximum Speed Law (
NMSL) in the United States was a provision of the
Federal 1974 Emergency Highway Energy Conservation Act that prohibited
speed limits higher than 55 miles per hour (90 km/h). It was drafted in response to oil price spikes and supply disruptions during the
1973 oil crisis.
While Federal officials hoped
gasoline consumption would fall by 2.2%, actual savings were estimated at between 0.5% and 1%. The reason for the low effectiveness was likely because:
A survey by the
Associated Press found that as of January 2, 1974:
- 12 states already had maximum speed limits of 55 mph (90 km/h).
- 9 states had maximum speed limits of 50 mph (80 km/h).
- 29 states had lower limits.
Insurance Institute for Highway Safety analysts wrote three papers that argued that increase from 55 to 65 mph (90 to 105 km/h) on rural roads led to a 25% to 30% increase in deaths (1/3 from increased travel, 2/3 from increased speed) while the full repeal in 1995 led to a further 15% increase in fatalities. In contrasting work, researchers at University of California Transportation Science Center argued that the interstates in question are only part of the equation, one also must account for traffic moving off the relatively more dangerous country roads and onto the relatively safer interstates. Accounting for this they found that raising rural speed limits to 65 mph (105 km/h) caused a 3.4% to 5.1% decrease in fatalities.