Frequencies for first 10,000 rows of pgm_prtcptn_cd variable in pos2003 dataset :

    program |
participati |
         on |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      4,413       44.13       44.13
          0 |         60        0.60       44.73
          1 |        540        5.40       50.13
          2 |      1,177       11.77       61.90
          3 |      3,810       38.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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