The fund generally will invest at least 80% of its total assets in the components of the index. The index is designed to measure the performance of U.S. Treasury Obligations with a maximum remaining maturity of less than or equal to 12 months. "U.S. Treasury Obligations" refer to securities issued or guaranteed by the U.S. Treasury where the payment of principal and interest is backed by the full faith and credit of the U.S. government. They include U.S. Treasury notes, bills and bonds.