Canadians make up the largest share.
Foreigners are buying more and more American houses. They spent $82.5 billion, about 10 percent of the home sales market, in 2011 alone. According to a survey from the National Association of Realtors, that's a 25 percent increase from 2010. Arizona, California, Florida and Texas are the most popular states for home-buying foreigners. But as The Economist reports, there is some location bias:
A state’s proximity to foreign markets also makes a difference: Europeans tend to purchase homes on the east coast, Asians on the west coast and South Americans in Florida. Canadians are the biggest buyers, accounting for 24% of sales to foreigners, more than double the proportion five years ago, before the housing crash.
The Chinese come in second place; Mexico and Britain's share both declined. See the full chart (and read more) here.