The PowerShares WilderHill Clean Energy Portfolio (Fund) is based on the WilderHill Clean Energy Index (Index). The Fund will normally invest at least 90% of its total assets in common stocks that comprise the Index. The Index is designed to deliver capital appreciation through the selection of companies that focus on greener and generally renewable sources of energy and technologies that facilitate cleaner energy. The Fund and the Index are rebalanced and reconstituted quarterly.