Zillow: U.S. homes gained $2 trillion in value this year

``The value of the entire U.S. housing stock increased by 6.5 percent -- or $2 trillion -- in 2017, according to a report from Zillow. All homes in the country are now worth a cumulative $31.8 trillion. The gain in home values was the fastest since 2013, when real estate was in the early stages of its recovery from the recession. Yet it still trails the surge in other assets, with the S&P 500 Index up about 19 percent, and bitcoin increasing exponentially.''