Frequencies for first 10,000 rows of buncreat variable in nhamcsed2013 dataset :

 BUN (Blood |
       urea |
nitrogen)/c |
  reatinine |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      8,115       81.15       81.15
        Yes |      1,885       18.85      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 7 Nov 2016