The fund uses a "passive management" approach to track the performance, before fees and expenses, of the index. Under normal circumstances, at least 80% of the fund"s net assets, plus borrowings for investment purposes, will be invested in the component securities of the index. The index consists primarily of common stocks of U.S. publicly traded real estate investment trusts that focus on owning commercial and residential mortgages and mortgage-backed securities and to a lesser extent, publicly traded closed-end funds. It is non-diversified.