Frequencies for first 10,000 rows of pgm_prtcptn_cd variable in pos2009 dataset :

    PROGRAM |
PARTICIPATI |
         ON |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      4,439       44.39       44.39
          1 |        567        5.67       50.06
          2 |        722        7.22       57.28
          3 |      4,272       42.72      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 17 May 2017