# Question: The following data describe the monthly volume for an urban

The following data describe the monthly volume for an urban courier service. Data are in thousands of pieces handled.

a. Construct a graph of the time series. Does the overall trend appear to be upward or downward?

b. Determine the three-month and five-month centered moving average curves and superimpose each on the original time series.

a. Construct a graph of the time series. Does the overall trend appear to be upward or downward?

b. Determine the three-month and five-month centered moving average curves and superimpose each on the original time series.

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