Home prices rose again in August, according to the S&P CoreLogic Case-Shiller U.S. National Home Price NSA Index, which showed a 1.4% seasonally adjusted increase from July and a 19.8% increase from a year earlier.

August’s annual gain was roughly flat with the pace of July’s increase, said Craig Lazzara, managing director and global head of index investment strategy at S&P Dow Jones Indexes.

Home-price gains were once again broadly distributed, as all 20 cities rose, although in most cases at a slower rate than had been the case a month ago, Lazzara said in a press release.

The 10-city composite index rose 0.9% on a monthly basis and 18.6% on a yearly basis, while the 20-city composite gained 1.2% monthly and 19.7% annually.

In Boston, home prices were up 0.5% on a monthly basis and 17.7% on an annual one.

Phoenix, San Diego, and Tampa, Fla., led the way in residential real estate price gains among the 20 metro areas in the index.

“We have previously suggested that the strength in the U.S. housing market is being driven in part by a reaction to the COVID pandemic, as potential buyers move from urban apartments to suburban homes,” Lazzara said, adding that more data is needed to understand whether the demand surge represents an acceleration of purchases that homebuyers would have made anyway, or reflects a secular change in locational preferences.

August’s data are consistent with either explanation, Lazzara noted, adding that the increases also suggest that the rise in home price growth, while still very strong, may be beginning to decelerate.