According to Swiss global financial services company UBS, their proprietary UBS Global Real Estate Bubble Index in select world cities has “increased significantly over the last five years”. Their research found that real house prices in the metro areas in their “bubble-risk zone” have climbed by almost 50% on average over the last 6 years. In some other major cities, prices have risen only about 15% over the same period. UBS states that falling mortgage rates over the last decade have led to the increase. The following graphic shows the cities with the greatest “bubble risk” at the top. At the other end of the spectrum, Chicago is the only very-large US city currently below fair value.