Frequencies for first 10,000 rows of drugres2 variable in person dataset :

  DRUG TEST |
  RESULTS-2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,808       98.08       98.08
          1 |         27        0.27       98.35
        155 |          1        0.01       98.36
        177 |          6        0.06       98.42
        187 |          1        0.01       98.43
        198 |          1        0.01       98.44
        208 |          3        0.03       98.47
        300 |          1        0.01       98.48
        304 |          3        0.03       98.51
        309 |          1        0.01       98.52
        321 |          3        0.03       98.55
        334 |          1        0.01       98.56
        351 |         15        0.15       98.71
        367 |          2        0.02       98.73
        401 |          2        0.02       98.75
        402 |          5        0.05       98.80
        407 |         11        0.11       98.91
        410 |          2        0.02       98.93
        417 |         35        0.35       99.28
        423 |          1        0.01       99.29
        600 |          2        0.02       99.31
        602 |          1        0.01       99.32
        603 |          4        0.04       99.36
        606 |          7        0.07       99.43
        695 |          1        0.01       99.44
        996 |         23        0.23       99.67
        999 |         33        0.33      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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