More evidence of Inc.’s second headquarters radically shifted the Northern Virginia housing market landscape: A new Redfin report has found Arlington and Alexandria to be the most the competitive housing markets in the country.

Seattle-based Redfin devises a score that rates how difficult it is for buyers to find a home using data on the number of competing offers and waived contingencies, as well as multiple listing service data on how quickly homes are going under contract and for how much above list price.

Homes sold in July left the market in a median 11 days in Arlington and 14 in Alexandria, compared to the 27-day median for all of Greater Washington and 38 days nationally, per the Redfin report.

In Arlington and Alexandria, the number of homes for sale fell by about 50% year-over-year in July. Nearly half, or 46%, of Arlington homes sold in July went for more than the list price compared to 27% a year ago. In Alexandria, 36% of homes sold for the more than the list price, up 12% from a year ago.

The two jurisdictions were given Redfin Compete Scores of 96, tied with Grand Rapids, Michigan, and just ahead of Tacoma, Washington, and Oakland, which were given scores of 95 and 93, respectively. Woodbridge was rated 92 as the ninth most competitive housing market.

The median sale price of all home types in the 22202 ZIP code was $995,000 in July, the highest for any month in a decade, according to data provided by MarketStats by ShowingTime based on listing activity from Bright MLS — backing up Redfin’s latest findings. The residential market looks very different nine months since Amazon (NASDAQ: AMZN) announced Arlington as the home of its second headquarters.

“If you believe home values will go up hundreds of thousands of dollars in the next five years, you will race to bid five or ten thousand dollars above asking price today,” Redfin chief economist Darly Fairweather said in a statement.