Select the data row or column of your sales revenue in the input area.

The damping coefficient should be between 0- 1, and it is suggested to choose 0.2 0.6 0.9 3 respectively.

Check the standard deviation and check the chart output, which is more intuitive.

Select the damping coefficient with the smallest error.

Drag fill handle in the cell of the last output number, and the number obtained is the forecast number of the next period.

Exponential smoothing lecture notes suggest reading Xu Guoxiang's statistical predictions and decisions.

Supplement:

The first column is the predicted value, n- 1 number. Drag this column.

The second column is the standard error, according to which to judge which damping coefficient is more appropriate, the smaller the standard error, the better.