"Even though the value of the average home in the U.S. increased by about $13,500 over the last year, thanks to declining interest rates it actually costs almost exactly the same in principal and interest each month to purchase as it did this time last year. Even taking into account the fact that affordability can vary - sometimes significantly - across the country based upon the different rates of home price appreciation we're seeing, that's a pretty incredible balancing act between interest rates and home prices at the national level... Right now, it takes 20 percent of the median monthly income to cover monthly payments on the median-priced home, which is well below historical norms." However, the report warns that affordability will be dramatically impacted by an increase in mortgage rates. "A half-point increase in interest rates would be equivalent to a $17,000 jump in the average home price, and bring that ratio to 21.5 percent. This increase is still below historical norms, but puts more pressure on homebuyers."