Personal consumption in transportation. 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 2010s. Year Expenditures 2009 879.7 2010 961.7 2011 1080.3 2012 1135.5 2013 1170.5 2014 1202.4 2015 1162.6 2016 1160.4 2017 1225.2 2018 1286.6 Source: Bureau of Transportation Statistics, US Dept. of Transportation, Table 3-16, 2019.