Frequencies for first 10,000 rows of prov0645 variable in pos2006 dataset :

    medical |
     school |
affiliation |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,710       87.10       87.10
          1 |         72        0.72       87.82
          2 |        109        1.09       88.91
          3 |         36        0.36       89.27
          4 |      1,073       10.73      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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