The Underlying Index seeks to reflect the performance of a selection of U.S.-dollar-denominated corporate bonds issued by companies that exhibit certain environmental, social and governance (ESG) characteristics, while also seeking to provide broad-market, core exposure to U.S.-dollar-denominated investment grade corporate bonds of U.S. and non‘U.S. issuers. The Underlying Index is designed to minimize tracking differences relative to the Northern Trust US Corporate Bond Index (the Parent Index) while also seeking (a) an aggregate higher scoring of certain ESG characteristics, as measured by the Northern Trust ESG Vector Score (ESG Vector Score) described below, and (b) reduction of aggregate climate-related risk, as measured by certain carbon-related risk metrics, each relative to its Parent Index. The Underlying Index also excludes certain companies by using controversial business involvement and norms-based screens.