div style="margin-top:6pt;"span style="color:#000000;font-family:arial;font-size:8.55pt"The Fund seeks to track the investment results of the ICE/spanspan style="color:#000000;font-family:arial;font-size:7pt;position:relative;top:-2pt"®/spanspan style="color:#000000;font-family:arial;font-size:8.55pt" U.S. Treasury 1-10 Year Bond Index (the /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"“/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"Underlying Index/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"”/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"), which measures /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"the performance of public obligations of the U.S. Treasury that have a remaining maturity of greater than one year and less than or equal to /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"ten years. As of March 31, 2026 there were 199 issues in the Underlying Index. /span/divdiv style="margin-top:6pt;"span style="color:#000000;font-family:arial;font-size:8.55pt"The Underlying Index consists of publicly issued U.S. Treasury securities that have a remaining maturity of greater than or equal to one /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"year and less than ten years and have $300 million or more of outstanding face value, excluding amounts held by the Federal Reserve /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"System. In addition, the securities in the Underlying Index must be fixed-rate and denominated in U.S. dollars. Excluded from the /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"Underlying Index are inflation-linked securities, Treasury bills, cash management bills, any government agency debt issued with or without /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"a government guarantee, original issue zero coupon securities and zero-coupon issues that have been stripped from coupon-paying bonds. /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"However, the amounts outstanding of qualifying securities are not reduced by any individual components of such securities (/spanspan style="color:#000000;font-family:arial;font-size:8.55pt;font-style:italic"i.e/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"., coupon or /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"principal) that have been stripped after inclusion in the Underlying Index. Securities issued or marketed primarily to retail investors do not /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"qualify for inclusion in the Underlying Index. The Underlying Index is market value weighted, and the securities in the Underlying Index are /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"updated on the last calendar day of each month./span br/ span style="color:#000000;font-family:arial;font-size:8.55pt;line-height:10.45pt" /span/divdiv style="margin-top:7pt;"span style="color:#000000;font-family:arial;font-size:8.55pt;line-height:10.45pt" /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"BFA uses an indexing approach to try to achieve the Fund’s investment objective. The Fund does not try to /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"“/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"beat/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"”/spanspan style="color:#000000;font-family:arial;font-size:8.55pt" the index it tracks and /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"does not seek temporary defensive positions when markets decline or appear overvalued./span/divdiv style="line-height:10.45pt;text-align:left;"span style="color:#000000;font-family:arial;font-size:8.55pt"Indexing may eliminate the chance that the Fund will substantially outperform the Underlying Index but also may reduce some of the risks /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"of active management, such as poor security selection. Indexing seeks to achieve lower costs and better after-tax performance by aiming /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"to keep portfolio turnover low in comparison to actively managed investment companies./span/divdiv style="margin-top:7pt;"span style="color:#000000;font-family:arial;font-size:8.55pt"BFA uses a representative sampling indexing strategy to manage the Fund. /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"“/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"Representative sampling/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"”/spanspan style="color:#000000;font-family:arial;font-size:8.55pt" is an indexing strategy that involves /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"investing in a representative sample of securities or other instruments that collectively has an investment profile similar to that of an /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"applicable underlying index. The instruments selected are expected to have, in the aggregate, investment characteristics (based on factors /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"such as market value and industry weightings), fundamental characteristics (such as return variability, duration (/spanspan style="color:#000000;font-family:arial;font-size:8.55pt;font-style:italic"i.e./spanspan style="color:#000000;font-family:arial;font-size:8.55pt", an instrument's price /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"sensitivity to a change in interest rates), maturity or credit ratings and yield) and liquidity measures similar to those of an applicable /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"underlying index. The Fund may or may not hold all of the components of the Underlying Index./span/divdiv style="margin-top:7pt;"span style="color:#000000;font-family:arial;font-size:8.55pt"The Fund will invest at least 80% of its assets in the component securities of the Underlying Index, and the Fund will invest at least 90% of /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"its assets in U.S. Treasury securities that BFA believes will help the Fund track the Underlying Index. The Fund will invest no more than 10% /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"of its assets in futures, options and swaps contracts that BFA believes will help the Fund track the Underlying Index. Cash and cash /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"equivalent investments associated with a derivative position will be treated as part of that position for the purposes of calculating the /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"percentage of investments included in the Underlying Index. The Fund seeks to track the investment results of the Underlying Index before /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"fees and expenses of the Fund./span/divdiv style="margin-top:7pt;"span style="color:#000000;font-family:arial;font-size:8.55pt"The Fund may lend securities representing up to one-third of the value of the Fund's total assets (including the value of any collateral /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"received)./span/divdiv style="margin-top:7pt;"span style="color:#000000;font-family:arial;font-size:8.55pt"The Underlying Index is sponsored by ICE Data Indices, LLC (the /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"“/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"Index Provider/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"”/spanspan style="color:#000000;font-family:arial;font-size:8.55pt" or /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"“/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"IDI/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"”/spanspan style="color:#000000;font-family:arial;font-size:8.55pt"), which is/spanspan style="color:#000000;font-family:arial;font-size:8.55pt;line-height:10.45pt" /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"independent of the Fund and BFA. The /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"Index Provider determines the composition and relative weightings of the components of the Underlying Index and publishes information /spanspan style="color:#000000;font-family:arial;font-size:8.55pt"regarding the market value of the Underlying Index./span/div