The bus and subway ridership for the summer months in London, England, have been recorded for the past 16 years.

a. We have found the trend line for the past data points; see plot below. And the trend line is characterized by the formula noted on the plot. Use trend projection method to forecast the ridership (how many) for the summer months in the year 17.

b. Now, the bus and subway ridership for the summer months is believed to be tied heavily to the number of tourists visiting the city. The regression line is plotted and characterized; see below. Please use linear regression model to forecast the ridership (how many) for the summer months in a year when the estimated number of tourists visiting is 18 millions

c. Please comment on the differences between trend projection method and linear regression method. In particular, which one do you think has more forecasting power?