The breakeven inflation rate represents a measure of expected inflation derived from 10-Year Treasury Constant Maturity Securities and 10-Year Treasury Inflation-Indexed Constant Maturity Securities. The latest value implies what market participants expect inflation to be in the next 10 years, on average.
Constant maturity is an adjustment for equivalent maturity, used by the Federal Reserve Board to compute indexes based on the average yield of various Treasury securities maturing at different periods.