U.S. home prices rose the most in 19 months in December, fueled by low mortgage rates and the tightest supply on record, according to Redfin.

Prices jumped 6.9% from a year earlier to a median of $312,500, the biggest annual increase since May 2018, the brokerage said in a report Friday. Values fell in just two of the 85 largest metropolitan areas Redfin tracks: New York, with a 2.4% decline, and San Francisco, down 1.7%.

Low borrowing costs and the strong economy brought buyers into the market, boosting competition for the slim supply of available homes, according to Daryl Fairweather, Redfin’s chief economist. Prices heated up in such West Coast areas as Seattle and Los Angeles, “which indicates the slowdown of 2019 has officially ended in these markets,” she said.

Some of the most-affordable cities in Redfin’s study had the biggest price gains, led by Memphis, Tennessee, with a 16% jump.

The inventory of available homes for sale nationwide tumbled 15% from a year earlier. There were fewer properties for sale last month than at any time since at least December 2012, the brokerage said.

“Many homeowners have refinanced their mortgages to take advantage of low interest rates and therefore feel committed to staying put,” Fairweather said. “The lack of homes for sale is going to fuel competition and price growth in 2020.”

This article was provided by Bloomberg News.