Frequencies for first 10,000 rows of physn_srvc_cd variable in pos2014 dataset 

  Services: |
  Physician |
       Code |      Freq.     Percent        Cum.
------------+-----------------------------------
          . |      9,300       93.00       93.00
          1 |        468        4.68       97.68
          2 |        215        2.15       99.83
          3 |         17        0.17      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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