Since year 2000, China's household debt has gone from 8% of GDP, to now 40% of GDP as a ratio (the US is 75% by comparison). Mortgage debt has become a common problem in China. At the rate household debt is expanding in China, they'll be up to 60% in four years or so.
http://www.bloomberg.com/news/articles/2013-02-19/china-hous...