The worst natural disaster in history was the flood of floods that occurred between July and August 1931 in central China. At the time, the Yangtze River overflowed and caused a series of floods. As a result, an estimated 3.7 million people died of illness, drowning, and starvation. According to the National Oceanic and Atmospheric Administration, more than 51 million people, a quarter of China's population at the time, were directly or indirectly affected by the floods.