There has been phenomenal growth in the transportation sector of the economy over the past decade. The personal consumption expenditure figures (in billions of dollars) over the past 10 years are given in the table below.

a. Compute exponentially smoothed values of this personal consumption time series, using the smoothing constants w = .2 and w = .8.

b. Plot the actual series and the two smoothed series on the same graph. Comment on the trend in personal consumption expenditure on transportation in the 2000s.

Year Expenditures

2006..............................1208.2

2007..............................1248.8

2008..............................1246.8

2009..............................1158.8

2010..............................1171.8

2011..............................1235.5

2012..............................1277.9

2013..............................1335.5

2014..............................1418.2

2015..............................1501.0