Frequencies for first 10,000 rows of prov6220 variable in pos2008 dataset :

       srv: |
  opthalmic |
    surgery |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      8,655       86.55       86.55
          0 |      1,234       12.34       98.89
          1 |         84        0.84       99.73
          2 |         18        0.18       99.91
          3 |          9        0.09      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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