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

  RAIL XING |
         ID |      Freq.     Percent        Cum.
------------+-----------------------------------
    0000000 |      9,961       99.61       99.61
    028459P |          1        0.01       99.62
    253600B |          1        0.01       99.63
    352071T |          1        0.01       99.64
    352121U |          1        0.01       99.65
    352275E |          1        0.01       99.66
    3522771 |          1        0.01       99.67
    352325F |          1        0.01       99.68
    426309E |          1        0.01       99.69
    433820U |          1        0.01       99.70
    438239B |          1        0.01       99.71
    500307S |          1        0.01       99.72
    597528N |          1        0.01       99.73
    6433045 |          1        0.01       99.74
    664089R |          1        0.01       99.75
    667109K |          1        0.01       99.76
    725201V |          1        0.01       99.77
    726719G |          1        0.01       99.78
    7277975 |          1        0.01       99.79
    731698B |          1        0.01       99.80
    731962G |          1        0.01       99.81
    741308N |          1        0.01       99.82
    741815W |          1        0.01       99.83
    745651W |          1        0.01       99.84
    749720R |          1        0.01       99.85
    750478G |          1        0.01       99.86
    750636E |          1        0.01       99.87
    752520K |          1        0.01       99.88
    752960B |          1        0.01       99.89
    810979D |          1        0.01       99.90
    906324H |          1        0.01       99.91
    9999999 |          9        0.09      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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