The investment seeks to track the investment results of the Bloomberg Barclays December 2021 Maturity Corporate Index which composed of U.S. dollar-denominated, investment-grade corporate bonds maturing in 2021. The fund generally will invest at least 90% of its assets in the component securities of the underlying index. The underlying index is composed of U.S. dollar-denominated, taxable, investment-grade corporate bonds scheduled to mature after December 31, 2020 and before December 16, 2021. -null-.