The fund is designed to track an all-cap index of US electric, gas, and water utility companies. The index is market cap-weighted and subject to capping limitations. The capping is designed to ensure diversification in its portfolio. Holdings are diversified by applying limits on regulated investment companies using the MSCI 25/50 methodology. The fund may also hold independent power producers, energy traders and companies engaged in electricity using renewable sources. The index is rebalanced on a quarterly basis.