Not new, but from Zillow and via Calculated Risk is a table of negative equity in the largest real estate markets in the US.
Phoenix: 68% of all mortgages are ‘under water’ calculated as the percentage of single family homes with mortgages where the equity value less than current market value.
The disparity is even wider in a real sense. I bet the proportion of properties in Phoenix that have mortgages in the first place is higher than in Pittsburgh. If true, the proportion of homes that are at risk in a financial sense is even lower here when compared to places like Phoenix. If we further compare the $ value of how much mortgages are underwater. I suspect the 6.8% of local properties are underwater in this type of calculation have total market values that are less than just the underwater amount in markets like Las Vegas. If that type of calculation were done, I bet the disparity between Phoenix and Pittsburgh could be more like 20:1.