Frequencies for first 10,000 rows of injprev variable in nhamcsopd2011 dataset :

     Injury |
 prevention |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,230       92.30       92.30
        Yes |        770        7.70      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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