Smoothed U.S. Recession Probabilities are derived from a dynamic-factor Markov-switching model applied to four monthly coincident variables: non-farm payroll employment, the index of industrial production, real personal income excluding transfer payments, and real manufacturing and trade sales. The model is based on a 1998 paper "An Economic Characterization of Business Cycle Dynamics with Factor Structure and Regime Switching" (International Economic Review, 1998, 39, 969–996). Recessions are usually determined retrospectively by the National Bureau of Economic Research (NBER). Indicators like this one can give a head start in identifying whether a recession may already be underway — before it is officially declared. Data sourced from FRED (Federal Reserve Bank of St. Louis).