Frequencies for first 10,000 rows of rail variable in accident dataset :

  RAIL XING |
         ID |      Freq.     Percent        Cum.
------------+-----------------------------------
    0000000 |      9,955       99.55       99.55
    0000002 |          1        0.01       99.56
    028395F |          1        0.01       99.57
    028623R |          1        0.01       99.58
    028705X |          1        0.01       99.59
    028755B |          1        0.01       99.60
    029598N |          1        0.01       99.61
    02B81BH |          1        0.01       99.62
    244622C |          1        0.01       99.63
    351473W |          1        0.01       99.64
    352125w |          1        0.01       99.65
    352325F |          1        0.01       99.66
    352329H |          1        0.01       99.67
    438166T |          1        0.01       99.68
    440575K |          1        0.01       99.69
    620752k |          1        0.01       99.70
    622845L |          1        0.01       99.71
     624298 |          1        0.01       99.72
    625566B |          2        0.02       99.74
    627659c |          1        0.01       99.75
     628090 |          1        0.01       99.76
    636542T |          1        0.01       99.77
    668056S |          1        0.01       99.78
    7253315 |          1        0.01       99.79
    727862V |          1        0.01       99.80
    731747V |          1        0.01       99.81
    731839H |          1        0.01       99.82
    747270P |          1        0.01       99.83
    747310K |          1        0.01       99.84
    751237W |          1        0.01       99.85
    751295S |          1        0.01       99.86
    754992N |          1        0.01       99.87
    760753C |          1        0.01       99.88
    787838H |          1        0.01       99.89
    788993J |          1        0.01       99.90
    804345T |          1        0.01       99.91
    810910H |          1        0.01       99.92
    843931T |          1        0.01       99.93
    865132A |          1        0.01       99.94
    9999999 |          6        0.06      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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