According to a new study using data from the U.S. Geological Survey, 71 million housing units are at high risk when it comes to natural disasters like tornados, earthquakes, or hurricanes. That represents 55 percent of the country's total homes. About 10.6 million are at a very high risk. The report, from RealtyTrac, used historical and predictive data to compile a county-by-county map that shows the likelihood of a county being hit by a devastating hurricane, tornado, or earthquake. "It's fairly obvious from looking at the map that these high-risk areas tend to be places where a lot of people want to live, like along the coast," said Daren Blomquist, vice president at RealtyTrac. However, the highest-risk parts of the country are in what's called "tornado alley" which covers Kansas, Nebraska, Oklahoma, and northern Texas.