The data set EXPREV contains information on a company's monthly expenses and revenues for two regions of the United States. 
data exprev;
   input Region $ State $ Month monyy5.
         Expenses Revenues;
   format month monyy5.;
   datalines;
Southern GA JAN95 2000  8000
Southern GA FEB95 1200  6000
Southern FL FEB95 8500 11000
Northern NY FEB95 3000  4000
Northern NY MAR95 6000  5000
Southern FL MAR95 9800 13500
Northern MA MAR95 1500  1000
;