A convenience store recently started to carry a new brand of soft drink. Management is interested in estimating future sales volume to determine whether it should continue to carry the new brand or replace it with another brand. The following table provides the number of cans sold per week. Use both the trend projection with regression and the exponential smoothing (let

=0.4

with an initial forecast for week 1 of 594)

methods to forecast demand for week 13.

Compare these methods by using the mean absolute deviation and mean absolute percent error performance criteria. Does your analysis suggest that sales are trending and if so, by how much?

Period	1	2	3	4	5	6	7	8	9	10	11	12
Sales	594	636	657	741	674	639	756	709	728	733	684	759

What is the forecast for week 13?

Find the mean absolute deviation (MAD)

Find the mean absolute percent error (MAPE).

(ii) Now obtain the exponential smoothing forecast.