Frequencies for first 10,000 rows of opthmlgy_srgry_sw variable in pos2011 dataset :

 Specialty: |
Opthamology |      Freq.     Percent        Cum.
------------+-----------------------------------
            |        354        3.54        3.54
          N |      9,428       94.28       97.82
          Y |        218        2.18      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Apr 2019