ETS

ETS (Error, Trend, Seasonality) is a forecasting model that decomposes a time series into error, trend, and seasonal components.

Number of time steps in a season.
Using a fixed random seed allows for reproducible result.
Several parameter combinations are known to be unstable (AMN, AMA, AMdN, AMdA, AMM, AMdM, MMA, MMdA, ANM, AAM, AAdM).
Unstable combinations are likely to fail when training and scoring.
Input data must be strictly positive when using multiplicative error, trend or seasonal components.
Damped trend requires at least one Trend parameter to be different from None.