Asset class size power rankings are rankings between U.S.-listed asset class size ETFs on certain investment-related metrics, including 3-month fund flows, 3-month return, AUM, average ETF expenses and average dividend yields. The metric calculations are based on U.S.-listed ETFs that are classified by ETF Database as being mostly exposed to a specific asset class size. If an ETF changes its asset class size classification, it will also be reflected in the investment metric calculations. The calculations exclude inverse ETFs.