Year 1: Demand 51

Year 2: Demand 50

Year 3: Demand 54

Year 4: Demand 55

Year 5 : Demand 58

Begin error measurent in year 3.

1.use exponential smothing 0.6 and 0.9, let initial forecast for year 1 be 51 same as the actual demand.

2. 2 year moving average

3. two year weighted moving average using weights 0.6 and 0.4 with more recent data given more weight