Consider a portion of monthly return data on 20-year Treasury Bonds from 2006-2010. The full data set can be found on the text website, labeled Treasury Bonds
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a. Plot the above series and discuss its seasonal variations.
b. Construct the seasonal indices for the data.
c. Estimate a linear trend model to the seasonally adjusted series.
d. Use the trend and seasonal estimates to make forecasts for the first three months of 2011.