Just prior to the 1973 oil crisis, Germany, Switzerland, and Austria all had no general speed restriction on autobahns. During the crisis, like other nations, Germany imposed temporary speed restrictions; for example, on autobahns effective 13 November 1973. Automakers projected a 20% plunge in sales, which they attributed in part to the lowered speed limits. The 100 km/h limit championed by Transportation Minister Lauritz Lauritzen lasted 111 days. Adjacent nations with unlimited speed autobahns, Austria The upper house insisted on a recommended limit until a thorough study of the effects of a mandatory limit could be conducted. Accordingly, the Federal Highway Research Institute conducted a multiple-year experiment, switching between mandatory and recommended limits on two test stretches of autobahn. In the final report issued in 1977, the Institute stated the mandatory speed limit could reduce the autobahn death toll but there would be economic impacts, so a political decision had to be made due to the trade-offs involved. At that time, the Federal Government declined to impose a mandatory limit. The fatality rate trend on the German autobahn mirrored those of other nations' motorways that imposed a general speed limit.