XME tracks an index that provides exposure across the broad market-cap spectrum of metals and mining segment in the United States, as classified by the GICS sector classification scheme. The metals and mining segment is composed of aluminum, coal and consumable fuels, copper, diversified metals and mining, gold, precious metals and minerals, silver, and steel. The fund is equal-weighted, adjusted to constituent weights that ensures concentration and liquidity requirements. The index is rebalanced quarterly.