The PowerShares Senior Loan Portfolio (Fund) is based on the S&P/LSTA U.S. Leveraged Loan 100 Index (Index). The Fund will normally invest at least 80% of its total assets in the component securities that comprise the Index. The Index is designed to track the market-weighted performance of the largest institutional leveraged loans based on market weightings, spreads and interest payments. The Fund and the Index are rebalanced and reconstituted bi-annually, in June and December.