Frequencies for first 10,000 rows of toxscren variable in nhamcsed2010 dataset :

 Toxicology |
     screen |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,516       95.16       95.16
        yes |        484        4.84      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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