The investment seeks investment results that correspond generally to the price and yield performance, before fees and expenses, of the Barclays U.S. Long Government/Credit Bond Index. The fund generally invests at least 80% of its assets in the securities of the underlying index or in depositary receipts representing securities in the underlying index. The underlying index is a sub-index of the Barclays U.S. Aggregate Bond Index and provides exposure to securities in the long maturity range of the Barclays U.S. government/Credit Bond Index.