An estimate of future demand. A forecast can be constructed using quantitative methods, qualitative methods, or a combination of methods, and it can be based on extrinsic (external) or intrinsic (internal) factors. Various forecasting techniques attempt to predict one or more of the four components of demand: cyclical, random, seasonal, and trend. Also see: Box- Jenkins Model, Exponential Smoothing Forecast, Extrinsic Forecasting Method, Intrinsic Forecasting Method, Qualitative Forecasting Method, Quantitative Forecasting Method.