(RECAP: Housing affordability hit its lowest level in nearly six years in June as home prices continued to climb, according to a report from the National Association Realtors. In June, the average mortgage payment represented 16.3% of household income, the highest since 2008. Excluding the last six years, it is lower than any time since at least 1989. Since most Americans take out a mortgage to buy a home, affordability is a function of both prices and interest rates. The median home price of $223,300 in June was the highest August 2007. Mortgage rates averaged 4.2% in June, up from 3.7% one year earlier. The drop in affordability helps explain why housing demand has been weaker so far this year.)