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

 drug test- |
 result (3) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,698       96.98       96.98
        151 |          1        0.01       96.99
        155 |         11        0.11       97.10
        156 |          1        0.01       97.11
        167 |          4        0.04       97.15
        177 |          6        0.06       97.21
        187 |          4        0.04       97.25
        189 |         12        0.12       97.37
        300 |          5        0.05       97.42
        304 |          5        0.05       97.47
        316 |          2        0.02       97.49
        321 |         11        0.11       97.60
        337 |          2        0.02       97.62
        343 |          2        0.02       97.64
        348 |          1        0.01       97.65
        351 |         12        0.12       97.77
        352 |          8        0.08       97.85
        367 |          4        0.04       97.89
        376 |          1        0.01       97.90
        401 |         16        0.16       98.06
        402 |          6        0.06       98.12
        407 |          6        0.06       98.18
        410 |          8        0.08       98.26
        417 |         24        0.24       98.50
        600 |         20        0.20       98.70
        603 |          5        0.05       98.75
        605 |         31        0.31       99.06
        695 |         20        0.20       99.26
        702 |          1        0.01       99.27
        996 |         73        0.73      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016