The Great Smoky Mountain National Park on the border of Tennessee and North Carolina is America’s most popular national park with more than nine million visitors each year. Suppose the National Park Service would like to forecast the number of visitors to this park in 2018. The Excel file Great Smoky Mountain.xlsx contains the number of visitors each year, in millions, to this park from 2002 until 2017.

a. Construct a graph showing the number of visitors each year visiting the Great Smoky Mountain National Park over time.

b. Forecast the number of visitors each year visiting the Great Smoky Mountain National Park in 2018 using a trend projection.

c. Interpret the meaning of the slope for the trend projection forecast.

d. Calculate the MAD for the forecast in part b.

e. Check for the presence of auto-correlation in the forecasting model using α = 0.05.