Frequencies for first 10,000 rows of veventnum variable in vevent dataset :

    vehicle |
      event |
     number |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      4,158       41.58       41.58
          2 |      2,148       21.48       63.06
          3 |      1,524       15.24       78.30
          4 |        955        9.55       87.85
          5 |        570        5.70       93.55
          6 |        309        3.09       96.64
          7 |        172        1.72       98.36
          8 |         75        0.75       99.11
          9 |         36        0.36       99.47
         10 |         18        0.18       99.65
         11 |         10        0.10       99.75
         12 |          6        0.06       99.81
         13 |          1        0.01       99.82
         14 |          1        0.01       99.83
         15 |          1        0.01       99.84
         16 |          1        0.01       99.85
         17 |          1        0.01       99.86
         18 |          1        0.01       99.87
         19 |          1        0.01       99.88
         20 |          1        0.01       99.89
         21 |          1        0.01       99.90
         22 |          1        0.01       99.91
         23 |          1        0.01       99.92
         24 |          1        0.01       99.93
         25 |          1        0.01       99.94
         26 |          1        0.01       99.95
         27 |          1        0.01       99.96
         28 |          1        0.01       99.97
         29 |          1        0.01       99.98
         30 |          1        0.01       99.99
         31 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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