The number of people who could afford to purchase median-priced homes in the Los Angeles region slipped in August from the year-earlier period but rose one percentage point from August, the California Association of Realtors said.

The monthly California Housing Affordability Index, a measure of home affordability based on home prices, income and mortgage rates and other housing costs, showed that 13 percent of Los Angeles households could afford to purchase a median-priced home in August, down from 17 percent a year earlier.

The index is largely dependent on median home prices, which dropped to $560,990 in September from $458,590 one year earlier, according to the CAR. In August, the median home price in L.A. County was $564,340.

Statewide, 15 percent of the population could afford to buy a home, down from 19 percent in the year-ago period and up one percentage point from August’s 14 percent. The median home price statewide in September was $543,980, versus $463,630 a year earlier and down from $568,730 in August.

The areas with the highest levels of affordability were the High Desert, which includes Palmdale and Lancaster, with 26 percent of households qualifying, and Sacramento, at 20 percent. The least affordable market was the Northern Wine Country region, where only 7 percent of households could afford to buy a median-priced home. Santa Barbara County’s South Coast area had the most expensive homes, where the median price was nearly $1.5 million in September.

Nationwide, the median home price dipped to $212,000 in September.