Frequencies for first 10,000 rows of drugtst2 variable in person dataset :

  DRUG TEST |
     TYPE-2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,750       97.50       97.50
          1 |         90        0.90       98.40
          2 |         21        0.21       98.61
          3 |         27        0.27       98.88
          7 |          2        0.02       98.90
          8 |        109        1.09       99.99
          9 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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