Answer in an Excel spreadsheet

Case Study 2 (Specialty Packaging Inc.): This case study is on demand forecasting and is detailed at the end of chapter 7 in the course text. The case requires you to analyze the given quarterly historical data from years 1 to 5, select an appropriate method of forecasting and then use the selected method to forecast the quarterly demand for years 6 to 8 . There are two approaches to achieve the objectives of this case. Approach 1 is the easy approach that would require you to plot and analyze the historical data. A plot of the historical data will reveal the presence of a trend and seasonality which rules all methods other that static method and Winter's model as appropriate methods. You can then use one of these methods to develop the required forecasts. Approach 2 is the harder but a more appropriate approach. In this approach you will use error analysis to generate forecast and error (MAD, MSE, MAPE) using all available methods (static, moving average, exponential moving average, Holt's model and Winter's model) and recommend the use of method with the least error. In addition, you will determine the tracking signal and compare it to the tracking limit (+/-6) to make sure that you are not overly over-forecasting or under-forecasting. I don't expect you to start from scratch and therefore I have uploaded a copy of the Tahoe Salt excel file under module 6. You can replace the historical data in this file with the historical data given in the case study for your analysis. The text book explains the workings of all methods using the Tahoe Salt example in chapter 7