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

  DRUG TEST |
     TYPE-1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      7,286       72.86       72.86
          1 |      1,133       11.33       84.19
          2 |        204        2.04       86.23
          3 |         97        0.97       87.20
          7 |         82        0.82       88.02
          8 |         28        0.28       88.30
          9 |      1,170       11.70      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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