Question: Select a firm of interest to you and obtain at least three continuous years of quarterly sales figures from the firm's annual reports at your library or on the Internet.

a. Draw a time-series graph and comment on the structure you see.

b. Compute the 1-year moving average; draw it on your graph, and comment.

c. Compute the seasonal indexes, graph them, and comment.

d. Compute and graph the seasonally adjusted series; then comment on what you see. In particular, what new information have you gained through seasonal adjustment?

e. Compute the trend line and personalize it to find forecasts for 2 years into the future. Graph these forecasts along with the original data. Comment on how reasonable these forecasts seem to you.