Frequencies for pminute variable in parkwork dataset :

 crash time |
   (minute) |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         50        4.41        4.41
          1 |         13        1.15        5.56
          2 |         14        1.24        6.80
          3 |          7        0.62        7.41
          4 |         11        0.97        8.38
          5 |         24        2.12       10.50
          6 |         11        0.97       11.47
          7 |         21        1.85       13.33
          8 |         16        1.41       14.74
          9 |         13        1.15       15.89
         10 |         35        3.09       18.98
         11 |         16        1.41       20.39
         12 |         18        1.59       21.98
         13 |          9        0.79       22.77
         14 |          9        0.79       23.57
         15 |         29        2.56       26.13
         16 |         10        0.88       27.01
         17 |         15        1.32       28.33
         18 |         14        1.24       29.57
         19 |         25        2.21       31.77
         20 |         34        3.00       34.77
         21 |         13        1.15       35.92
         22 |          5        0.44       36.36
         23 |         28        2.47       38.83
         24 |         11        0.97       39.81
         25 |         24        2.12       41.92
         26 |         10        0.88       42.81
         27 |         18        1.59       44.40
         28 |         19        1.68       46.07
         29 |         25        2.21       48.28
         30 |         64        5.65       53.93
         31 |         15        1.32       55.25
         32 |         10        0.88       56.13
         33 |          9        0.79       56.93
         34 |         16        1.41       58.34
         35 |         43        3.80       62.14
         36 |         15        1.32       63.46
         37 |         11        0.97       64.43
         38 |         12        1.06       65.49
         39 |         10        0.88       66.37
         40 |         36        3.18       69.55
         41 |         17        1.50       71.05
         42 |         17        1.50       72.55
         43 |         11        0.97       73.52
         44 |         13        1.15       74.67
         45 |         51        4.50       79.17
         46 |          9        0.79       79.96
         47 |         15        1.32       81.29
         48 |         13        1.15       82.44
         49 |         11        0.97       83.41
         50 |         33        2.91       86.32
         51 |         13        1.15       87.47
         52 |          9        0.79       88.26
         53 |         27        2.38       90.64
         54 |          8        0.71       91.35
         55 |         34        3.00       94.35
         56 |         12        1.06       95.41
         57 |         23        2.03       97.44
         58 |         15        1.32       98.76
         59 |         12        1.06       99.82
         99 |          2        0.18      100.00
------------+-----------------------------------
      Total |      1,133      100.00

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