Frequencies for first 10,000 rows of paydk variable in namcs2015 dataset :

   Expected |
  source of |
payment for |
     visit: |
    Unknown |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,701       97.01       97.01
          1 |        299        2.99      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 25 Oct 2017