Whatcom home affordability declines in third quarter

The strong demand for Whatcom County houses this summer and fall is driving down affordability.

The local housing affordability index was 129.4 during the third quarter, down from 132.2 from a year ago. This is according to newly released data from the Runstad Center for Real Estate Studies, which is based at the University of Washington.

The affordability index measures the ability of a typical family to make payments on a median-price home.

What does Whatcom's latest index number mean? A family earning the median income has 29.4 percent more income than the bare minimum required to qualify to buy a median-price home, with a 20 percent down payment and a 30-year mortgage. Along with home sales price and income, interest rates are factored into the index.

The number of Whatcom County homes sold last quarter was up 12.8 percent compared to a year earlier.

Across Washington the housing affordability index was 138.9 in the third quarter, down from 143 a year earlier. Among the bigger counties in Washington, King County had the lowest index number at 101.9 while Benton County had the highest, at 183.6.

This story was originally published December 1, 2015 at 3:51 PM with the headline "Whatcom home affordability declines in third quarter."