Frequencies for first 10,000 rows of phys variable in nhamcsopd2009 dataset :

  physician |
       seen |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      1,924       19.24       19.24
        yes |      8,076       80.76      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016