Frequencies for first 10,000 rows of rept_cod_num variable in demo2004q1 dataset :

          rept_cod_num |      Freq.     Percent        Cum.
-----------------------+-----------------------------------
            DIR Direct |      1,461       14.61       14.61
EXP Expedited (15-Day) |      7,726       77.26       91.87
          PER Periodic |        813        8.13      100.00
-----------------------+-----------------------------------
                 Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Dec 2015