The correlation of REITs to the stock market can change. REITs were once considered highly uncorrelated to stocks. However, in 2008, once the economy entered recession, the correlation gap narrowed. In that year, the Vanguard REIT Index Exchange Fund, which is representative of trading in the REIT sector, lost 38 percent, which was just as much as the largest companies that trade in the stock market, according to a 2012 "Wall Street Journal" article. In fact, in the 10-year period leading up to 2012, the correlation between REITs and the stock market doubled, the article indicated.