U.S. home prices continue to surge ahead as homebuyer demand exceeds listing inventory.

The median home price rose a record 21% to $348,500 for the four-week period ending May 2, compared to the same time period in 2020, according to a report Friday from Redfin.

Houses spent an average of only 19 days on the market for the four-week period, an all-time low, the data showed. That’s down 16 days for the same time last year. 

Meanwhile, intense competition is driving homes to close above their initial asking prices. The typical home sold for 1.4% above its list price during the same four weeks. About 48% of residences sold for more than their asking price, up 20% compared the same month in 2020 and a record high. 

“Right now we are seeing a substantial increase in home prices, which could be a precursor to more widespread inflation throughout the economy,” Redfin’s chief economist Daryl Fairweather said in the report. “A more balanced market could encourage more move-up homeowners to finally sell, because they won’t be so fearful about being able to find and compete for a home to buy.”

In April 2020, the economic shutdowns designed to curb the Covid-19 virus were in place, “which makes year-over-year comparisons unreliable for select housing metrics,” the report noted. Some metrics were compared to the same time period in 2019 for that reason. 

That includes data on pending home sales, which rose 23% in the four-week period ending May 2 compared to the same period in 2019.

In addition, active listings plummeted 48% during those four weeks compared to the same month in 2019, Redfin found.