Frequencies for first 10,000 rows of rept_cod_num variable in demo2010q4 dataset :

          rept_cod_num |      Freq.     Percent        Cum.
-----------------------+-----------------------------------
            DIR Direct |        433        4.33        4.33
EXP Expedited (15-Day) |      7,810       78.10       82.43
          PER Periodic |      1,757       17.57      100.00
-----------------------+-----------------------------------
                 Total |     10,000      100.00

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