Frequencies for first 10,000 rows of harm_ev variable in vehicle dataset :

      First |
    Harmful |
      Event |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        836        8.36        8.36
          2 |          1        0.01        8.37
          3 |         17        0.17        8.54
          5 |         74        0.74        9.28
          6 |          1        0.01        9.29
          7 |         13        0.13        9.42
          8 |      1,192       11.92       21.34
          9 |        150        1.50       22.84
         10 |        105        1.05       23.89
         11 |         15        0.15       24.04
         12 |      5,287       52.87       76.91
         13 |         28        0.28       77.19
         14 |        157        1.57       78.76
         16 |         22        0.22       78.98
         17 |        109        1.09       80.07
         18 |          8        0.08       80.15
         19 |        121        1.21       81.36
         20 |        402        4.02       85.38
         21 |         73        0.73       86.11
         22 |        262        2.62       88.73
         23 |        113        1.13       89.86
         24 |        194        1.94       91.80
         25 |         27        0.27       92.07
         26 |         64        0.64       92.71
         27 |        346        3.46       96.17
         28 |        222        2.22       98.39
         29 |         36        0.36       98.75
         31 |        115        1.15       99.90
         99 |         10        0.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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