"If we could choose only one family of funds for the ideal 401(k) plan, it would be Dimensional Fund Advisors. We believe DFA's institutional index funds are the best, and employees whose plans include them are fortunate...In 2001, a portfolio of DFA funds weighted equally among the asset classes we listed above would have appreciated by 1 percent. Doesn't seem like much but it's much better than the 12 percent loss in the Standard & Poor's 500 Index and the 23 percent decline by the average large-company growth fund."