As the American home front was converting industry to wartime production, numerous problems arose. The revived economy brought jobs and better income to the U.S population, and people were eager to spend their earnings on new consumer goods, including the latest automobiles. Busy meeting this demand, automobile manufacturers were slow to convert their assembly lines from car production to tank and warplane production. Although the automobile factories were crucial to government production plans, the manufacture of automobiles actually increased by almost one million from 1939 to 1941. However, in its first meeting in early 1942 the federal War Production Board (WPB) outlawed civilian car and truck production so that military production could proceed. Despite this move it still took several months for military production to improve as automobile manufacturers sought various exemptions and extensions for conversion. President Roosevelt, however, was patient with the automobile manufacturers, realizing that he needed their cooperation for the long term. In the end, Packard was contracted to build nine thousand airplane engines, Chrysler to build tanks, and Ford to produce bombers.