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Times are good for those at the top: Twenty major U.S. counties saw double-digit price gains in June—many breaking records—according to the realtor.com® Luxury Home Index. And while one turbocharged market continued to dominate the top 20, its runner-up was quite a surprise.

Of course, what’s luxury in one area is commonplace in another. The index actually analyzes the entry-level luxury price tier, or the top 5% of all residential sales, in 90 counties. In 50 of those counties, the luxury tier starts at $1 million. Some markets have higher starting prices: San Francisco’s is a whopping $3.3 million.

“The strong stock market and economy gives luxury buyers additional cash,” says Danielle Hale, chief economist at realtor.com. “And real estate is a great way to spend that cash.”

Challenging the notion that what goes up must come down, the Sarasota County market in Florida continued to experience the fastest home-price growth, as it has since March. Prices increased 21% in June compared with the period one year earlier. Even with loftier prices, higher-end homes in Sarasota sell quickly. Half of all luxury homes in the area sold within 165 days in August, up 22% from the year before.

Greg Owens, president of the Realtor Association of Sarasota and Manatee, says the luxury market is doing well as more people move to the area. Owens, who is also operating principal of Keller Williams on the Water in Sarasota, says the healthy economy and the new federal rules on state taxes may be encouraging people to move to Florida.

“Beaches never get boring,” says Owens. “We are on the Gulf of Mexico. Where would you rather live?”

The surprising runner-up is the county of Queens in New York, humble hometown of the Mets, Archie Bunker, and Donald Trump. Sales of homes worth $1.3 million or more jumped 15.5% in June from the year-earlier period.

“Now you’re seeing people wearing Queens hats and T-shirts,” says Eric Benaim, a…