BBBI is designed to mirror the performance of corporate bonds within the lower half of the investment-grade spectrum. Specifically, the fund targets BBB-rated, fixed-rate, USD-denominated corporate bonds with remaining maturities of five years or more but less than ten years. With a market value-weighted approach, the index includes bonds from both US and non-US issuers, particularly those in the industrial, utility, and financial sectors. Up to 20% of the investments may comprise futures, options, swaps, US Treasuries, cash and cash equivalents, and securities of other companies, including ETFs. Additionally, the fund will hold privately issued securities. The index undergoes rebalancing every month on the last business day.