The War Production Board (WPB) was an agency of the United States government that supervised war production during World War II. President Franklin D. Roosevelt established it in January 1942, with Executive Order 9024. The WPB replaced the Supply Priorities and Allocations Board and the Office of Production Management. The WPB directed conversion of companies engaged in activities relevant to war from peacetime work to war needs, allocated scarce materials, established priorities in the distribution of materials and services, and prohibited nonessential production. It rationed such commodities as gasoline, heating oil, metals, rubber, paper, and plastics. It was dissolved shortly after the defeat of Japan in 1945 and was replaced by the Civilian Production Administration in late 1945. In 1942–1945, WPB supervised the production of $183 billion (equivalent to $ in ) worth of weapons and supplies, about 40 percent of the world output of munitions. The UK, the USSR, and other allies produced an additional 30 percent, while the Axis produced only 30 percent. One fourth of the US output was warplanes; one fourth was warships. Meanwhile, the civilian standard of living was about level. Organization The first chair of the Board was Donald Nelson, who served from 1942 to 1944. He was succeeded by Julius Albert Krug, who served from 1944 until the Board was dissolved. The national WPB constituted the chair, the Secretaries of War, Navy, and Agriculture, the lieutenant general in charge of War Department procurement, the director of the Office of Price Administration, the Federal Loan Administrator, the chair of the Board of Economic Warfare, and the special assistant to the President for the defense aid program. The WPB had advisory, policy-making, and progress-reporting divisions. The WPB employed mathematicians who were responsible for constructing and maintaining multilevel models of resources needed for the war effort. Their models included manufacturing defects, materials lost when ships were sunk at sea, &c. Upon analyzing field reports which revealed systematic shortages, the mathematicians decided to increase allocations submitted to the board by a factor of 10. The WPB managed 12 regional offices and operated 120 field offices throughout the nation. They worked alongside state war production boards, which maintained records on state war production facilities and also helped state businesses obtain war contracts and loans. The national WPB's primary task was converting civilian industry to war production. The WPB assigned priorities and allocated scarce materials such as steel, aluminum,