Frequencies for first 10,000 rows of drugtst1 variable in person dataset :

  drug test |
  -type (1) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,255       62.55       62.55
          1 |      3,516       35.16       97.71
          2 |         59        0.59       98.30
          3 |          4        0.04       98.34
          7 |         22        0.22       98.56
          8 |         32        0.32       98.88
          9 |        112        1.12      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016