Frequencies for first 10,000 rows of prov0645 variable in pos1998 dataset :

    medical |
     school |
affiliation |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,805       88.05       88.05
          1 |         72        0.72       88.77
          2 |        112        1.12       89.89
          3 |         42        0.42       90.31
          4 |        969        9.69      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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