How are qualitative method, regression method, multiple equation method, and moving average method are used in forecasting?

1. Do you think that forecasting based on the arithmetical average of a given number of past data will be a correct forecasting for a business trend? Would you please tell us how qualitative method, regression method, multiple equation method, and moving average method are used in forecasting? What types of data do you need for the above forecasting method?

2. Would you please tell us how a manager can use his/her knowledge in Economic indices in strategic planning of a company?

3. Would you please tell us whether the CPIs for individual areas can be used to compare living costs among the areas?