Frequencies for first 10,000 rows of rail variable in accident dataset : RAIL XING | ID | Freq. Percent Cum. ------------+----------------------------------- 0000000 | 9,922 99.22 99.22 003211G | 1 0.01 99.23 025132G | 1 0.01 99.24 025468Y | 1 0.01 99.25 025651J | 1 0.01 99.26 025915C | 1 0.01 99.27 026070P | 2 0.02 99.29 026578S | 1 0.01 99.30 028394Y | 1 0.01 99.31 028459P | 1 0.01 99.32 028585J | 1 0.01 99.33 028650M | 1 0.01 99.34 028688J | 1 0.01 99.35 028714W | 1 0.01 99.36 029854C | 1 0.01 99.37 057190R | 1 0.01 99.38 253607Y | 1 0.01 99.39 272492H | 1 0.01 99.40 304231A | 1 0.01 99.41 304256V | 1 0.01 99.42 327480Y | 1 0.01 99.43 330360H | 1 0.01 99.44 351228t | 1 0.01 99.45 352246U | 1 0.01 99.46 426054K | 1 0.01 99.47 426309E | 1 0.01 99.48 434944R | 1 0.01 99.49 437949K | 1 0.01 99.50 531632Y | 1 0.01 99.51 621029M | 1 0.01 99.52 622337W | 1 0.01 99.53 622828V | 1 0.01 99.54 624775F | 1 0.01 99.55 624820x | 1 0.01 99.56 625571x | 1 0.01 99.57 628165L | 1 0.01 99.58 628169N | 1 0.01 99.59 643833A | 1 0.01 99.60 661959E | 1 0.01 99.61 668137S | 1 0.01 99.62 725363X | 1 0.01 99.63 725816M | 1 0.01 99.64 728249H | 1 0.01 99.65 731788A | 1 0.01 99.66 745997Y | 1 0.01 99.67 749946C | 1 0.01 99.68 750619N | 1 0.01 99.69 750641B | 1 0.01 99.70 751291P | 1 0.01 99.71 752748K | 1 0.01 99.72 757240A | 1 0.01 99.73 787736P | 1 0.01 99.74 834994U | 1 0.01 99.75 908367h | 1 0.01 99.76 912060D | 1 0.01 99.77 999999 | 1 0.01 99.78 9999999 | 22 0.22 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016