Stock mutual funds fell for the third of the past four weeks, this time led lower in the stock market by small-cap core and midcap value funds, which fell 3.26% and 3.17%, according to Lipper Inc. Large-cap value ended the week with the top year-to-date gain of 5.07% among nonleveraged diversified stock mutual funds. Small-cap growth limped in near the bottom, with a 5.38% decline.