The fund is passively managed to provide broad exposure to the largest companies in the US by market capitalization. Companies are selected by using shares outstanding (both total and free-float) and capitalization-based breakpoints to determine those that are considered mega-cap from the broader CRSP US Total Market Index. The resulting portfolio is a very representative take on the mega-cap space. The underlying index encompasses equity securities including common stocks and real estate investment trusts (REITs) that are listed on a CRSP exchange of interest. Holdings are market cap-weighted, subject to a quarterly review.