If you want a prediction, go to the lady in the tent at the local fair.
If you want a forecast, talk to those who have an intimate knowledge of the drivers of the outcomes you are seeking to forecast.
Good forecasting is an iterative process, the more you do, the better you get, so long as you understand why the forecast is (almost) never right on each occasion it is done. Continuous improvement techniques are the core functions of good forecasting, and good forecasting is essential to smooth operations.
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