Comments on Gardner's new state of the art paper

These notes supplement Gardner's comprehensive update of his 1985 state of the art paper on the exponential smoothing methods of forecasting. A general definition of exponential smoothing, accommodating both linear and nonlinear versions of this method, is presented. Damped trend corrected exponential smoothing, augmented by a long-run growth rate, is also proposed for time series that display long term secular trends.