Frequencies for first 10,000 rows of exam variable in nhamcsopd2010 dataset :

  exam code |
       from |
   icd-9-cm |
 procedures |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      8,126       81.26       81.26
        yes |      1,874       18.74      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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