After initial attacks from high-altitude precision bombing in which less than 10% of the bombs fell near their targets, Allied air forces switched to low-level night-time incendiary attacks against Japanese cities. On the night of 9–10 March 1945, 16 square miles of downtown Tokyo were burned out and tens of thousands were killed by U.S. Army Air Forces B-29s. (The Survey estimated that 88,000 died, while the Tokyo Fire Department estimated 97,000. Historian Richard Rhodes estimated more than 100,000, though journalist Mark Selden considered even this figure to be too low.) In the following 10 days, a total of 31 square miles were destroyed. The Survey notes that these attacks had little direct effect on manufacturing, with factories that were hit by bombs having less drop off in production than those that did not. However, they also noted that production dropped by 54% during this period due to the effects of bombing: the killing, injuring and dehousing of the workers as well as the destruction of the transportation network. They noted a precipitous reduction in food availability as well, dropping from about 2,000 calories per day at the start of the war, to 1,680 for industrial workers at the height of the campaign, and less for non-essential workers.