Weighted Moving Average. Use Excel Spreadsheet (Copy the table below and Paste it into Excel). Your manager is trying to determine what forecasting method to use. Based upon the following historical data, calculate the following forecast and specify what procedure you would utilize. Calculate the weighted three-month moving average for period 6 using weights of 0.40 (for the period t-1); 0.30 (for the period t-2), and 0.30 (for the period t-3). (Do not round intermediate calculations. Round your answers to 1 decimal place.) Month 1 2 3 4 5 6 7 8 9 10 11 12 Actual Demand 52 55 57 67 73 75 76 77 77 79 80 82