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

  DRUG TEST |
     TYPE-1 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,699       66.99       66.99
          1 |      1,484       14.84       81.83
          2 |        114        1.14       82.97
          3 |        237        2.37       85.34
          7 |         67        0.67       86.01
          8 |         37        0.37       86.38
          9 |      1,362       13.62      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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