The fund allocates a minimum of 80% of its portfolio to holdings that mirror the underlying index. Furthermore, at least 90% of its capital is dedicated to U.S. Treasury securities, which BFA strategically selects to ensure close alignment with the index's performance. The benchmark index itself is comprised of publicly issued U.S. government debt instruments, all of which are scheduled to mature between January 1, 2022, and December 15, 2022. This fund operates with a non-diversified investment approach.