The Fund seeks to track the investment results of the Bloomberg MSCI US Aggregate ESG Focus Index (the Underlying Index), which has been developed by Bloomberg Finance L.P. and its affiliates (the Index Provider or Bloomberg) with environmental, social and governance (ESG) rating inputs from MSCI ESG Research LLC (MSCI ESG Research) pursuant to an agreement between MSCI ESG Research and Bloomberg Index Services Limited (a subsidiary of Bloomberg) or an affiliate. The Underlying Index is an optimized fixed-income index designed to reflect the performance of U.S. dollar-denominated, investment-grade (as determined by the Index Provider) bonds from issuers generally evaluated for favorable ESG practices (as determined by MSCI ESG Research), while seeking to exhibit risk and return characteristics similar to those of the Bloomberg US Aggregate Bond Index (the Parent Index).