Frequencies for first 10,000 rows of payself variable in namcs2011 dataset :

   Self pay |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,476       94.76       94.76
        Yes |        524        5.24      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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