Therefore Jaqui had decided to develop a seasonally adjusted regression model for the import

beer sales data. Jaqui's data set can be found on the Website that accompanies the text under

the filename BEER$1$ xIs.

$1.$ She needs your help to construct a simple weighting method for developing the seasonal

factors, to create a linear trend line for the import beer sales over time, and then combine

the two in order to forecast sales for $2005.$