English: During the Manhattan Project, the final stage of uranium enrichment was performed by the Y-12 plant at Oak Ridge, Tennessee. The "product" was then shipped to Los Alamos for machining and casting. This graph shows the volume of product shipped to Los Alamos under the auspices of the Manhattan Project, which lasted until its abolishment at the end of December 1946 (at which point the US Atomic Energy Commission took over all of its property and operations). Note that the enrichment level of the uranium on this graph is not equal: the uranium shipped in 1944, for example, had an average enrichment level no higher than 70.6% (per page 4 in the same document this chart came from). By July 1945, this average had been raised to 81.6%, and by December 29, 1946, the average enrichment level of the 1,041,026.5 grams of uranium shipped was "Approx. 95%"

The graph indicates several milestones:

• First Beta Product Shipment (June 1944): The Y-12 facility consisted of an Alpha and Beta tracks in separate building. Alpha began operation in late 1943/early 1944. Beta began operation in March 1944. The Alpha process would enrich the uranium to about 10% U-235.
• K-25 Feed to Alpha (March 1945): K-25 was the gaseous diffusion uranium enrichment facility at Oak Ridge. Originally, K-25 and Y-12 were considered independent methods to enrich uranium. However in early 1945, it was realized that the inefficiencies of K-25 (at that time) were such that it would be better to use it to pre-enrich uranium that was then sent to Y-12. This indicates when the K-25 feed was added to the Alpha process, when it was initially only very minimally enriched.
• K-25 Feed to Beta (June 1945): Indicates when the K-25 feed was added to the Beta process, at which point it was already enriched to 20-25%, decreasing the amount of separative work that Y-12 had to do dramatically.
• Hiroshima (August 1945): The Little Boy bomb's final pieces were sent to Tinian at the end of July 1945, and consisted of 64 kilograms of (on average) 80% enriched uranium. The weapon was dropped on Hiroshima on 6 August 1945. At the time it was dropped, as the graph indicates, it contained essentially all of the US enriched uranium supply. If another Little Boy bomb was to be made, the graph implies that sufficient fuel would have been available by October 1945.

The overall appendix has the date "10/7/47" written on its cover, though it may have been written earlier than this (it contains data through December 31, 1946).