The Vintage Restaurant, on Captiva Island near Fort Myers, Florida, is owned and operated by Karen Payne. The restaurant just completed its third year of operation. During that time, Karen sought to establish a reputation for the restaurant as a high-quality dining establishment that specializes in fresh seafood. Through the efforts of Karen and her staff, her restaurant has become one of the best and fastest-growing restaurants on the island. To better plan for future growth of the restaurant, Karen needs to develop a system that will enable her to forecast food and beverage sales by month for up to one year in advance. Table 6.17 shows the value of food and beverage sales ($1000s) for the first three years of operation. Month Sales

table attached

analysis of the sales data for the Vintage Restaurant:

1.A time series plot. Comment on the underlying pattern in the time series.

2.Using the dummy variable approach, forecast sales for January through December of the fourth year.

My question. I am stuck on question number 2. I got as far as standard deviation, but I cannot figure out how to do the seasonal index.