Frequencies for first 10,000 rows of biopsy variable in nhamcsopd2005 dataset :

     biopsy |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,891       98.91       98.91
        yes |        109        1.09      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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