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

  DRUG TEST |
  RESULTS-2 |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,787       97.87       97.87
          1 |         36        0.36       98.23
        155 |          1        0.01       98.24
        167 |          2        0.02       98.26
        177 |          1        0.01       98.27
        187 |          1        0.01       98.28
        208 |          1        0.01       98.29
        304 |          1        0.01       98.30
        308 |          1        0.01       98.31
        321 |          1        0.01       98.32
        343 |          1        0.01       98.33
        349 |          1        0.01       98.34
        351 |          5        0.05       98.39
        367 |          1        0.01       98.40
        401 |         10        0.10       98.50
        402 |          5        0.05       98.55
        405 |          1        0.01       98.56
        407 |         16        0.16       98.72
        417 |         43        0.43       99.15
        600 |          3        0.03       99.18
        603 |          1        0.01       99.19
        605 |          1        0.01       99.20
        606 |          5        0.05       99.25
        695 |          1        0.01       99.26
        702 |          2        0.02       99.28
        795 |          1        0.01       99.29
        996 |          2        0.02       99.31
        997 |          2        0.02       99.33
        998 |          9        0.09       99.42
        999 |         58        0.58      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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