The pace of housing-price gains in Boston quickened in March, according to the S&P CoreLogic Case-Shiller U.S. National Home Price NSA Index, which showed a 2.6% increase from February and a 14.9% increase from a year earlier, compared to a gain of 0.9% the previous month.

Housing inventory in the Boston area, meanwhile, remained below year-ago levels in April.

The number of buyers who locked in mortgage rates for second homes spiked to 178% year over year in April, according to a report from Redfin.