22 Here are the data for the past 21 months for actual sales of a particular product:

Develop a forecast for the fourth quarter using three different focus forecasting rules. (Note that to correctly use this procedure, the rules are first tested on the third quarter; the best-performing one is used to forecast the fourth quarter.) Do the problem using quarters, as opposed to fore- casting separate months.

Transcribed Image Text:

2004 2005 January 300 275 February 400 375 March 425 350 April 450 425 May 400 400 June 460 350 July 400 350 August 300 275 September 375 350 October 500 November 550 December 500