iShares iBonds Dec 2027 Term Treasury ETF (IBTH US) – Portfolio Construction MethodologyThe underlying ICE 2027 Maturity US Treasury Index (USD) offers a rules-based basket of U.S. Treasury notes/bonds with final maturities in calendar year 2027. Eligible securities are USD-denominated, fixed-rate, non-inflation-linked Treasuries; TIPS, STRIPS, floaters, and perpetuals are excluded. Constituents are market-value weighted and maintained on a monthly schedule: new qualifying issues enter at month-end subject ...