Frequencies for first 10,000 rows of copd variable in namcs2013 dataset :

       Does |
patient now |
 have: COPD |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,580       95.80       95.80
        Yes |        420        4.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017