Value investing is back — and no one’s happier about that than John Rogers. Rogers is CEO and chairman of Chicago-based Ariel Investments, which says it’s the oldest Black-owned money manager in the country. Founded in 1983, it invests in small- and mid-cap value stocks. Ariel Fund, the $16 billion firm’s flagship mutual fund, returned 78 percent over the 12 months through May 31, as value stocks have rebounded from 12 years in the doldrums. That performance puts the fund in the ninth percentile of mid-cap value funds for the past year, according to research firm Morningstar. Value stocks began outperforming growth in October, and Rogers, 63, maintains the party is just beginning. According to data compiled by Ariel, periods when value outperforms growth last 33 months on average, going back to 1926.