Frequencies for first 10,000 rows of ckd variable in nhamcsed2015 dataset :

       Does |
    patient |
      have: |
    Chronic |
     kidney |
    disease |
      (CKD) |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,720       97.20       97.20
        Yes |        280        2.80      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Nov 2017