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

  DRUG TEST |
     TYPE-2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,376       93.76       93.76
          1 |        430        4.30       98.06
          2 |         47        0.47       98.53
          3 |         25        0.25       98.78
          8 |          5        0.05       98.83
          9 |        117        1.17      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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