The fund offers exposure to the US small-cap space by investing in S&P SmallCap 600 stocks. This covers the 901st through the 1500th securities of the S&P Total Market Index (parent index). With its fixed 600 constituents, ZSML provides a purer exposure to small-caps as it excludes most midcap securities. The fund may also invest in various industry groups without any sector bias as long as it provides a sector balance between the underlying index and the parent index. With this, the Committee compares the weight of each GICS sector in the index to its weight in the relevant market-cap range of the S&P Total Market Index. Securities are further screened for size, liquidity, and financial viability measures. Holdings are then weighted by market-cap and rebalanced on a quarterly basis.