The file Coffee Exports contains the coffee exports (in thousands of 60 kg bags) by Costa Rica from 2004 to 2018.
a. Plot the data.
b. Fit a three-year moving average to the data and plot the results.
c. Using a smoothing coefficient of W = 0.50, exponentially smooth the series and plot the results.
d. What is your exponentially smoothed forecast for 2019?
e. Repeat (c) and (d), using a smoothing coefficient of W = 0.25.
f. Compare the results of (d) and (e).
g. What conclusions can you reach about the exports of coffee in Costa Rica?