Home sales slumped in the second quarter despite what was likely the strongest period for U.S. growth in years, the latest sign that the economic expansion faces headwinds.

Existing-home sales slipped 0.6% in June from the previous month to a seasonally adjusted annual rate of 5.38 million, the National Association of Realtors said Monday. Compared with a year earlier, sales in June declined 2.2%.

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