U.S. house price growth decelerated for the second consecutive month, posting a 19.7% increase year over year in May, a slight fall from April's 20.6% growth, according to the S&P CoreLogic Case-Shiller U.S. National Home Price NSA Index. The index was up 1.0% from the previous month after seasonal adjustment.

Despite the price slowdown, growth rates remain "extremely robust," with the three composite indices resting at or above the 98th percentile historically, according to S&P Dow Jones Indices Managing Director Craig Lazzara.

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Lazzara noted that mortgage financing has become even more expensive after the Fed raised interest rates, and added that the "extraordinary home price growth" might no longer be supported in a tougher macroeconomic environment.

Price deceleration in top cities

The slowdown was also reflected in both the 20-City Composite Index and the 10-City Composite Index. The 20-City Composite Index saw a year-over-year gain of 20.5% in May, down from the previous month's 21.2%, while the 10-City Composite Index saw a 19.0% increase year over year, also a slight drop from 19.6% in April.

For the third consecutive month, Tampa, Fla., posted the highest annual house price gain at 36.1%. Miami followed with an annual house price hike of 34.0%, while Dallas rounded out the top three cities with a 30.8% price increase.

Top homebuilder, residential mortgage lender

U.S. homebuilder stocks are still down, closing July 25 with a median total return of negative 19.3% over the course of one year.

Taylor Morrison Home Corp. had a better performing stock than the rest of U.S. homebuilders, with a one-year total return of 7.8%. In the 12 months to March 31, the company sold 13,646 homes, an 8.4% increase from the previous year.

Rocket Mortgage LLC remained the top U.S. residential mortgage lender year-to-date, originating $58.69 billion in residential mortgages through April. This was down 52.3% from the same period in the previous year.

Home sales, starts fall MOM in June

New single-family home sales in the U.S. dropped 8.1% on a monthly basis in June to a seasonally adjusted annual rate of 590,000 units, according to data from the U.S. Census Bureau and the U.S. Department of Housing and Urban Development. On an annual basis, new home sales fell 17.4%.

Likewise, existing-home sales saw a 5.4% decline from the previous month and a 14.2% drop year over year, according to the National Association of Realtors.

Privately owned, single-unit housing starts also fell by 8.1% month over month in June and by 15.7% on a yearly basis.

In a July 20 press release, National Association of Realtors Chief Economist Lawrence Yun said that potential home buyers are continuously affected by the declining housing affordability. "Both mortgage rates and home prices have risen too sharply in a short span of time," he added.

While there are more houses now in the market, Yun said that the record-low pace of days on market indicates a vague view on house prices. "Homes priced right are selling very quickly, but homes priced too high are deterring prospective buyers," Yun said.

S&P Dow Jones Indices and S&P Global Market Intelligence are owned by S&P Global Inc.