By Dan Weil Forward price-earnings multiples for small-cap stocks have been this low only twice in the last 20 years. Small-cap stocks have taken it on the chin recently. The Russell 2000 Index of mostly small-cap stocks has slid 10.2% in the last six months, almost doubling the 5.4% decline for the Russell 1000 Index of mostly large-cap stocks. Part of that reflects “outright risk aversion since the New Year,” Cormac Weldon, manager of U.K. money manager Artemis’ U.S. Smaller Companies fund. That would include reaction to the Russia-Ukraine war. “But periods of outright risk aversion tend to …