“At least a fifth of all occupied single-family homes were rentals last year in 32 of the nation’s top metropolitan regions, according to a USA TODAY analysis of U.S. Census Bureau data. That’s up from seven metros in 2006. The growth reflects changes brought by the housing boom and bust and the enduring financial hardships imposed by the recession. Millions of homeowners lost homes to foreclosure and were forced to become renters, while others delayed homeownership. Nationwide, 18% of occupied single-family homes last year were rentals, up from nearly 15% in 2006, show data based on the American Community Survey, an annual Census Bureau survey.”