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Sales of ultra-luxury homes surged in New York, Miami and Palm Beach, Florida, in the second quarter, even as they fell in much of the rest of the world, according to a new report.

The number of homes that sold for $10 million or more in the second quarter jumped 44% in Palm Beach, 27% in Miami and 16% in New York, according to a report from real estate firm Knight Frank.

New York led the U.S. in $10 million-plus sales, with 72, its highest total in two years, according to the report. Miami came in second with 55, followed by Los Angeles with 42 and Palm Beach with 36. Los Angeles saw a 29% decline in $10 million-plus sales, due largely to the new "mansion tax," which adds a 5.5% charge on homes sold for over $10 million, the report said.

The biggest sale of the quarter was the $150 million deal in May for Palm Beach's only private island, reportedly purchased by Australian infrastructure investor Michael Dorrell, according to The Wall Street Journal. In June, a historic 3.2-acre estate in Palm Beach sold for $148 million, while in Manhattan, the penthouse of the Aman New York was sold for $135 million in July.

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