Housing markets across the world, from the U.K. to China to Australia, are losing steam, holding back prospects for the global economy that last year grew at its slowest rate since the financial crisis. Across 23 countries, an index of inflation-adjusted home prices compiled by the Federal Reserve Bank of Dallas grew 1.8% in the third quarter of 2019 from a year earlier, down from a recent peak of 4.3% in 2016, according to an Oxford Economics analysis. In 18 large economies, world-wide residential investment dropped on a…