To answer the question above, firstly based on the monthly sales data of Year $1,2,3,4$ and $5,$ you should forecast the $12$ monthly demands of Year $6$ from January to December using "moving average", "simple exponential smoothing", "Holts' model", and "Winter's model", respectively. Secondly, you should calculate the forecast$-$error indicators of bias, TS$,$ MAD, MAPE, and MSE regarding these four models. Thirdly, based on your findings, you should identify the best forecasting methods and provide your justifications.

Two documents should be submitted for this assignment. The first is the Excel file in which the formula, the calculation processes and solutions of the four forecasting methods, and the related forecast$-$error estimates of bias, TS$,$ MAD, MAPE, and MSE should be given. The second is the word file template as report by answering questions asked in the report template. This word file template will be posted on D$2$L $($Note: Sample of the work in excel and Video recording of the tutorial is posted on D$2$L$)$