Manhattan Project: monthly expenditure 1942-1946

From August 1942 until the end of 1946, a total of 2.19 billion U.S. dollars was invested into the Manhattan Project. This project was responsible for the development of the first atomic weapons, and successfully achieved its goal in June 1945 during the Trinity Test, before the nuclear attacks on Hiroshima and Nagasaki in August that year. The bulk of this investment went into the uranium producing facilities in Oak Ridge Tennessee, as well as the plutonium producing facilities in Washington, while a much smaller share was allocated to the Los Alamos Laboratory where the bombs were developed. Spending on the project peaked in mid-1944, and then decreased over 1945, before the project was eventually taken over by the U.S. Atomic Energy Commission in January 1947.