The investment seeks to provide investment results that closely correspond, before fees and expenses, to the performance of the John Hancock Dimensional Mid Cap Index. The fund normally invests at least 80% of its net assets (plus any borrowings for investment purposes) in securities that compose the fund's benchmark index. The index is designed to comprise a subset of securities in the U.S. Universe issued by companies whose market capitalizations are between the 200th and 951st largest U.S. Company at the time of reconstitution.