iShares U.S. Healthcare ETF seeks to track the investment results of the Russell 1000 Health Care RIC 22.5/45 Capped Index composed of U.S. equities in the healthcare sector. The fund generally will invest at least 80% of its assets in the component securities of its underlying index and in investments that have economic characteristics that are substantially identical to the component securities of its underlying index. The underlying index measures the performance of the healthcare sector of the U.S. equity market. The fund is non-diversified.