DELISTED - The Fund, under normal circumstances, creates long positions by investing at least 80% of its assets in the securities that comprise the S&P MidCap® 400 Index (“Index”) and/or financial instruments that provide leveraged and unleveraged exposure to the Index. These financial instruments include: futures contracts; options on securities, indices and futures contracts; equity caps, floors and collars; swap agreements; forward contracts; short positions; reverse repurchase agreements; exchange-traded funds (“ETFs”); and other financial instruments. On a day-to-day basis, the Fund invests the remainder of its assets in money market funds or short-term debt instruments that have terms-to-maturity of less than 397 days and exhibit high quality credit profiles, including U.S. government securities and repurchase agreements.The Index measures the performance of the mid-cap segment of the U.S. equity universe. The Index is a capitalization-weighted index composed of 400 domestic common stocks. Standard & Poor’s® selects the 400 stocks comprising the Index on the basis of market values and industry diversification. The Index represents approximately 7% of the U.S. equities market. Component securities have capitalizations ranging from $950 million to $10.5 billion as of April 30, 2014. Components of the Index include companies in the financial services industry. The components of the Index and the percentages represented by certain industries in the Index may change over time. The Fund will concentrate its investment (i.e., hold 25% or more of its total assets in the stocks of a particular industry or group of industries) in a particular industry or group of industries to approximately the same extent as the Index is so concentrated.The Fund may gain leveraged exposure to only a representative sample of the securities in the Index that have aggregate characteristics similar to those of the Index. The Fund gains this exposure either by directly investing in the underlying securities of the Index or by investing in derivatives that provide leveraged exposure to those securities. The Fund invests in derivatives, which are financial instruments that derive value from the underlying reference asset or assets, such as stocks, bonds, or funds (including ETFs), interest rates or indexes. The Fund invests in derivatives as a substitute for investing directly in a security in order to gain leveraged exposure to the Index or its components. The Fund seeks to remain fully invested at all times consistent with its stated investment objective. At the close of the markets each trading day, Rafferty positions the Fund’s portfolio so that its exposure to the Index is consistent with the Fund’s investment objective. The impact of the Index’s movements during the day will affect whether the Fund’s portfolio needs to be re-positioned. For example, if the Index has risen on a given day, net assets of the Fund should rise, meaning that the Fund’s exposure will need to be increased. Conversely, if the Index has fallen on a given day, net assets of the Fund should fall, meaning the Fund’s exposure will need to be reduced. This re-positioning strategy typically results in high portfolio turnover.Because of daily rebalancing and the compounding of each day’s return over time, the return of the Fund for periods longer than a single day will be the result of each day’s returns compounded over the period, which will very likely differ from 200% of the return of the Index over the same period. The Fund will lose money if the Index performance is flat over time, and as a result of daily rebalancing, the Index’s volatility and the effects of compounding, it is even possible that the Fund will lose money over time while the Index’s performance increases. Additionally, because a significant portion of the assets of the Fund may come from investors using “asset allocation” and “market timing” investment strategies, the Fund may further need to engage in frequent trading.