The investment seeks to provide investment results that, before fees and expenses, correspond generally to the total return performance of an index derived from the health care equipment and supplies segment of a U.S. total market composite index. In seeking to track the performance of the S&P Health Care Equipment Select Industry Index (the index), the fund employs a sampling strategy. It generally invests substantially all, but at least 80%, of its total assets in the securities comprising the index. The index represents the health care equipment segment of the S&P Total Market Index (S&P TMI).