The file P12_46.xlsx contains monthly time series data for total U. S. retail sales of building materials, garden equipment, and supplies dealers. a. Is seasonality present in these data? If so, characterize the seasonality pattern and then deseasonalize this time series using the ratio-tomoving- average method.
b. If you decided to deseasonalize this time series in part a, forecast the deseasonalized data for each month of the next year using the moving average method with an appropriate span.
c. Does Holt’s exponential smoothing method, with optimal smoothing constants, outperform the moving average method employed in part b? Demonstrate why or why not.