The following data represent the average number of employees in outlets of a large consumer electronics retailer:

Year 2001 2002 2003 2004 2005 2006 2007 2008 2009 2010 Number 20.6 17.3 18.6 21.5 23.2 19.9 18.7 15.6 19.7 20.4

a. Construct a time-series plot of this time series. Does it appear that a linear trend exists in the time series?

b. Calculate forecasts for each of the years in the time series. Use a smoothing constant of 0.25 and single exponential smoothing.

c. Calculate the MAD value for the forecasts you generated in part b.

d. Construct a single exponential smoothing forecast for 2011. Use a smoothing constant of 0.25.