The U.S. home affordability index drop in August to 156.1 from a level of 160.7 in July according to the National Association of Realtors. Increase mortgage rates and the spike in home prices are fueling the deceleration in affordability. The interest rate on fixed rate 30-year mortgages was at 4.41 percent in August, compared to July that is a .3 percentage point increase. In addition, median home prices continue to hover around the $200,000 range.