San Diego County home prices rose 6.6 percent in the last year, said the S&P/Case-Shiller Home Price Index

San Diego County home prices rose 6.6 percent in the year ended in September, said the S&P/Case-Shiller Home Price Index released Tuesday.

Home prices locally exceeded the September-to-September national average increase of 4.9 percent. San Diego home prices showed a 6 percent increase year-over-year in August.

From August to September, the county’s home prices rose 0.6 percent, which outpaced the national average of 0.2 percent.

The fastest growing home prices in the index’s 20-city composite were in San Francisco (11.2 percent), Denver (10.9 percent) and Portland (10.1 percent). San Diego’s rise was around the same pace as Los Angeles, Tampa and Atlanta.

Chicago home prices grew the least year-over-year, at 1.1 percent. Other slow rising-cities were Washington, D.C., New York City and Cleveland.

University of San Diego economist Alan Gin said the county has seen a slowdown in the market because the local population is priced out.

All other indicators that should boost home prices — a reduction in distressed properties, very low housing supply, job growth and low interest rates — are up.

“There’s a limit to how high prices can go,” he said.

The countywide median home price was $456,760 in October, real estate data firm Corelogic said. Based on median earnings and ability to qualify for a mortgage, only 25 percent of homes in San Diego are considered within financial reach of residents, said the California Association of Realtors’ latest affordability study.

Gary Kent, a La Jolla-based agent with Keller-Williams, said the Case-Shiller numbers are already out of date and he is seeing changes on the ground. In addition to La Jolla, he sells properties in Pacific Beach, Clairemont, University City, Mission Valley, North Park, Mira Mesa, Normal Heights and other city areas.

He said he is seeing more price reductions, flexibility on prices from sellers, less demand and longer days on market.

“Six months ago, it was common to get multiple offers on a home and get full price,” he said. “That’s not happening now at all.”