Frequencies for first 10,000 rows of pgm_prtcptn_cd variable in pos2018 dataset :

    Program |
Participati |
    on Code |      Freq.     Percent        Cum.
------------+-----------------------------------
          . |      4,978       49.78       49.78
          1 |        512        5.12       54.90
          2 |        746        7.46       62.36
          3 |      3,764       37.64      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Feb 2019