Frequencies for first 10,000 rows of physn_srvc_cd variable in pos1994 dataset :

       srv: |
  physician |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      9,718       97.18       97.18
          1 |        245        2.45       99.63
          2 |         17        0.17       99.80
          3 |         20        0.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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