Portland-area home prices jumped again in January, pushed higher by a shortage of homes for sale.

Metro home prices rose four-tenths of a percent in January, according to the according to the S&P CoreLogic Case-Shiller home price index, reaching a level 7.1 percent higher than a year earlier.

Seattle led the 20-city index with a 12.9 percent year-over-year increase, followed by Las Vegas with an 11.1 percent increase. Seven of the cities in the index saw prices rising at a faster rate than Portland over the past year.

The national index rose 6.2 percent.

Portland's home prices continue to set new records. Prices are now 21 percent higher than the previous high-water mark, set in August 2007.

The growth of home prices, however, has slowed in recent months. Two years ago, prices were growing at a rate of 12 percent a year.

Last month, the median-priced home in the Portland area sold for $385,000, according to the Regional Multiple Listing Service.

Home prices have been pushed ever-higher by a low inventory of homes for sale. The small number of listings has left buyers to try to outbid one another.

Meanwhile, there's been little new construction of for-sale homes as the cost of land, construction materials and labor have escalated. Few homes are vacant.

The rising cost of homes, which far exceeds growth in wages, has curbed affordability in the Portland area, even with the extra boost of low mortgage rates.

But mortgage rates are on the upswing, which could further limit would-be homebuyers' means.

The Case-Shiller home price index uses repeat sales of the same homes to measure changes in values across the market. It's released as a three-month rolling average.

-- Elliot Njus

enjus@oregonian.com

503-294-5034

@enjus