Chapter 16, Problem 61PS

The monthly commercial and residential prices for natural gas (dollars per thousand cubic feet) the United States from January 2008 through December 2016 are stored in Natural Gas.

For the commercial price and the residential price,

a. do you think the price for natural gas has a seasonal component?

b. plot the time series. Does this chart support your answer in (a)?

c. compute an exponential trend forecasting equation for monthly data.

d. interpret the monthly compound growth rate.

e. interpret the monthly multipliers. Do the multipliers support your answer in (a) and (b)?

f. compare the results for the commercial prices and the residential prices.