The "Treasury Index" is an index based on auctions of U.S. Treasury bills, or on the U.S. Treasury's daily yield curve. It is often used in determining mortgage rates for adjustable rate mortgages and as a performance benchmark for investors in the capital markets. The calculations of treasury indexes and their components vary by the financial institution calculating the index. Components are typically based on the weighted average prices of five-year, ten-year and bond-futures contracts. Because the components have different investment time frames, each weighting, based on investment duration, is adjusted for equal contribution to the index.