To be able to receive full credit, you must show your computations in the space provided for each question.

Date	Percent
2013-01-01	5.60
2013-04-01	5.30
2013-07-01	5.40
2013-10-01	7.00
2014-01-01	6.20
2014-04-01	5.80
2014-07-01	6.00
2014-10-01	7.70
2015-01-01	6.90
2015-04-01	6.50
2015-07-01	6.70
2015-10-01	8.60
2016-01-01	7.60
2016-04-01	7.40
2016-07-01	7.60
2016-10-01	9.40
2017-01-01	8.44
2017-04-01	8.24
2017-07-01	8.43
2017-10-01	10.44
2018-01-01	9.34

1). Calculate the centered moving average (CMA) and show the time plot of quarterly e-commerce retail sales along with the centered moving-average forecasts based on a span of k=4. Make sure to include the labels of x and y axes and adjust the values on the plot to show the possible changes more clearly over the time. In the space provided below, show your plot, and compare and interpret the trend of two series.