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

       Does |
    patient |
      have: |
 History of |
  pulmonary |
   embolism |
 (PE), deep |
       vein |
 thrombosis |
       (DVT |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,872       98.72       98.72
        Yes |        128        1.28      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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