The U.S. Bureau of Labor Statistics provides data on the year-to-year percentage changes in the wages and salaries of workers in private industries, including both “white-collar” and “blue-collar” occupations. Here we consider these data for the years 1980-1996. The percentage changes of interest are in the file P2_56.XLS. Develop side-by-side boxplots to summarize these distributions of annual percentage changes. In particular, state and interpret the interquartile range for each of three given distributions.