Frequencies for first 10,000 rows of injury variable in nhamcsopd2009 dataset :

  is injury |
      visit |
   related? |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      8,805       88.05       88.05
        yes |      1,195       11.95      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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