Frequencies for drugtst1 variable in person dataset :

  DRUG TEST |
     TYPE-1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        669       62.12       62.12
          1 |        408       37.88      100.00
------------+-----------------------------------
      Total |      1,077      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016