Global supply chains-problem set time series forecasting

Create an Excel spreadsheet that fits a time series model (with level, linear trend, and seasonal components) for purposes of forecasting daily demand at Penguin. Include calculations necessary to determine forecast margin of uncertainty. Assume that forecast errors are normally distributed. 

Use your time series model to forecast future daily demand for the next three weeks (April 9-28), including a margin of uncertainty for each day’s forecast. Include a graph that shows information regarding the forecast. 

The assessment of your work will include the accuracy as well as the clarity of the spreadsheet and graph (e.g., clear labels, good alignment, easy to understand, etc.).