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

 Rail Grade |
    Xing ID |      Freq.     Percent        Cum.
------------+-----------------------------------
    0000000 |      9,933       99.33       99.33
    003640K |          1        0.01       99.34
    026068N |          1        0.01       99.35
    026741L |          1        0.01       99.36
    026763L |          1        0.01       99.37
    028778H |          1        0.01       99.38
    028798U |          1        0.01       99.39
    029845D |          1        0.01       99.40
    050362X |          1        0.01       99.41
    057152G |          1        0.01       99.42
    253773R |          1        0.01       99.43
    253800K |          1        0.01       99.44
    339696K |          1        0.01       99.45
    339797N |          1        0.01       99.46
    341768L |          1        0.01       99.47
    347012F |          1        0.01       99.48
    349N59Y |          1        0.01       99.49
    425347K |          1        0.01       99.50
    434217M |          1        0.01       99.51
    434422T |          1        0.01       99.52
    437718C |          1        0.01       99.53
    437975A |          1        0.01       99.54
    438168C |          1        0.01       99.55
    438553K |          1        0.01       99.56
    500623P |          1        0.01       99.57
    600703J |          1        0.01       99.58
    620641T |          1        0.01       99.59
    62125IV |          1        0.01       99.60
    622454A |          1        0.01       99.61
    622626X |          1        0.01       99.62
    622657W |          1        0.01       99.63
    624338K |          1        0.01       99.64
    624350P |          1        0.01       99.65
    626479B |          1        0.01       99.66
    627296L |          1        0.01       99.67
    628116P |          1        0.01       99.68
    628168G |          1        0.01       99.69
    628279Y |          1        0.01       99.70
    637315R |          1        0.01       99.71
    637346P |          1        0.01       99.72
    639454T |          1        0.01       99.73
    663221H |          1        0.01       99.74
    725374K |          1        0.01       99.75
    727092B |          1        0.01       99.76
    741357K |          1        0.01       99.77
    741714K |          1        0.01       99.78
    745838S |          1        0.01       99.79
    747872F |          1        0.01       99.80
    750966K |          2        0.02       99.82
    760847D |          1        0.01       99.83
    78771OM |          1        0.01       99.84
    787753F |          1        0.01       99.85
    804363R |          1        0.01       99.86
    804595F |          1        0.01       99.87
    833775G |          1        0.01       99.88
    853816N |          1        0.01       99.89
    856654Y |          1        0.01       99.90
    868320A |          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