Frequencies for first 10,000 rows of injury variable in nhamcsed1997 dataset :

   is visit |
 related to |
  injury or |
 poisoning? |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,323       63.23       63.23
          1 |      3,677       36.77      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016