Each quarter, HSH.com publishes a report that looks at the annual income required to quality for a residential mortgage in the 50 largest metropolitan areas in the United States. To do this, they look at the median home price for each city and then apply a 28% debt-to-income ratio (principal and interest payments divided by before tax salary). They also assume a 20% down payment and a 30-year fixed-rate mortgage. In their latest report, that comes with an interest rate of 3.15%.

Below is a chart showing what they consider to be the 10 most affordable and the 10 least affordable metros (chart via the New York Times). I don't think the cities on this list will necessarily surprise many of you (though I didn't think Pittsburgh was this affordable), but it is interesting to see it all quantified. It's also worth thinking about what might happen to these figures as that 3.15% number comes down. Shockingly, the price of highly-levered assets tends to be correlated with financing costs.