Frequencies for first 10,000 rows of drugres3 variable in person dataset :

  DRUG TEST |
  RESULTS-3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,919       99.19       99.19
        187 |          1        0.01       99.20
        208 |          1        0.01       99.21
        304 |          1        0.01       99.22
        308 |          1        0.01       99.23
        321 |          2        0.02       99.25
        343 |          2        0.02       99.27
        351 |          4        0.04       99.31
        367 |          3        0.03       99.34
        401 |          3        0.03       99.37
        407 |          6        0.06       99.43
        417 |          2        0.02       99.45
        423 |          1        0.01       99.46
        600 |          1        0.01       99.47
        606 |          2        0.02       99.49
        695 |          2        0.02       99.51
        996 |         14        0.14       99.65
        998 |          1        0.01       99.66
        999 |         34        0.34      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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