Frequencies for first 10,000 rows of mdcl_schl_afltn_cd variable in pos1996 dataset :

    medical |
     school |
affiliation |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,803       88.03       88.03
          1 |         74        0.74       88.77
          2 |        110        1.10       89.87
          3 |         43        0.43       90.30
          4 |        970        9.70      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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