When did the 55MPH speed limit take place?

Question

When did the 55MPH speed limit take place?

Answer 1

It came about in the early-mid 1970's and was an effort to reduce energy consumption.

Answer 2

After the Arab/Israeli war in 1973, OPEC put an embargo on their oil exports that resulted in huge lines at the gas pumps...A measure taken by the US government to conserve oil and fuel was to reduce the speed limit on federal highways (Interstates) from 65 to 55 mph...(It cut down on the number accidents and fatalities on the highways, too)

Answer 3

1974