Frequencies for first 10,000 rows of biopsy variable in nhamcsopd2006 dataset :

     biopsy |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,890       98.90       98.90
        Yes |        110        1.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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