Create a separate section of the report for each BY group, and sum the values for the selected variables. The BY statement produces a separate section of the report for each BY group. The SUM statement alone sums the values of Price and Quantity for the entire data set. Because the program contains a BY statement, the SUM statement also sums the values of Price and Quantity for each BY group that contains more than one observation.

   by sale_type order_date;
   sum price quantity;