Frequencies for first 10,000 rows of toxscren variable in nhamcsed2011 dataset :

 Toxicology |
     screen |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,437       94.37       94.37
        Yes |        563        5.63      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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