Automotive History.

Economically, the seventies were marked by the energy crisis which peaked in 1973 and 1979 (see 1973 oil crisis and 1979 oil crisis). After the first oil shock in 1973, gasoline was rationed in many countries. Europe particularly depended on the Middle East for oil; the U.S. was also affected even though it had its own oil reserves. Many European countries introduced car-free days. In the U.S., customers with a license plate ending in an odd number were only allowed to buy gasoline on odd-numbered days, while even-numbered plate-holders could only purchase gasoline on even-numbered days.