Frequencies for drugtst3 variable in person dataset :

  DRUG TEST |
     TYPE-3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      1,074       99.72       99.72
          1 |          3        0.28      100.00
------------+-----------------------------------
      Total |      1,077      100.00

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