The investment seeks to track, as closely as possible, before fees and expenses, the price and yield performance of the MVIS® Moody's Analytics® US Investment Grade Corporate Bond Index. The fund normally invests at least 80% of its total assets in securities that comprise the fund's benchmark index. The inndex is comprised of U.S. dollar-denominated corporate bonds issued in the U.S. domestic market that have an investment grade rating based on the bond's composite rating, which is an average of ratings from various rating agencies. It is non-diversified.