Frequencies for first 10,000 rows of prov1670 variable in pos2001 dataset :

    program |
participati |
         on |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      4,067       40.67       40.67
          0 |         63        0.63       41.30
          1 |        554        5.54       46.84
          2 |      1,738       17.38       64.22
          3 |      3,578       35.78      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 26 Jan 2016