For the Hawkins Company, the monthly percentages of all shipments received on time over the past 12 months are 80, 82, 84, 83, 83, 84, 85, 84, 82, 83, 84, and 83.

a. Construct a time series plot. What type of pattern exists in the data?

b. Compare the three-month moving average approach with the exponential smoothing approach for α .2. Which provides more accurate forecasts using MSE as the measure of forecast accuracy?

c. What is the forecast for next month?