Under normal market conditions, the fund seeks to achieve its investment objective primarily through investing at least 80% of its assets (net assets plus the amount of any borrowings made for investment purposes) in underlying exchange-traded funds ("ETFs"). An ETF is an investment fund that is traded on a stock exchange and holds an underlying basket of securities generally designed to track an index. ETFs can be bought and sold through the trading day in the secondary market or at net asset value directly with an authorized participant.