Stock mutual funds rallied from a two-week slide. U.S. diversified stock funds, according to Lipper Inc. data, jumped 1.37% in the latest week, which ended Dec. 18. Small-cap growth funds, which have been year-to-date laggards, led the charge in the latest week, leaping 2.08%. They’re up 1.37% for the year. The year-to-date leaders, with a 13.14% gain, were S&P 500 index funds, which track the proxy for the broad stock market.