Frequencies for first 10,000 rows of rail variable in accident dataset : Rail Grade | Xing ID | Freq. Percent Cum. ------------+----------------------------------- 0000000 | 9,901 99.01 99.01 0000009 | 20 0.20 99.21 000000O | 1 0.01 99.22 003612G | 1 0.01 99.23 026517B | 1 0.01 99.24 026529V | 1 0.01 99.25 026560G | 1 0.01 99.26 026672F | 1 0.01 99.27 027957V | 1 0.01 99.28 028209C | 1 0.01 99.29 028391D | 1 0.01 99.30 028819K | 1 0.01 99.31 029056E | 1 0.01 99.32 272387G | 1 0.01 99.33 272467A | 1 0.01 99.34 272533K | 1 0.01 99.35 272910W | 1 0.01 99.36 335656Y | 1 0.01 99.37 352105K | 1 0.01 99.38 426147E | 1 0.01 99.39 434224X | 1 0.01 99.40 434557Y | 1 0.01 99.41 435001K | 1 0.01 99.42 437590J | 1 0.01 99.43 437823D | 1 0.01 99.44 437929Y | 1 0.01 99.45 437958J | 1 0.01 99.46 500541H | 1 0.01 99.47 500564P | 1 0.01 99.48 516095N | 1 0.01 99.49 531633F | 1 0.01 99.50 531648V | 1 0.01 99.51 600731M | 1 0.01 99.52 625882Y | 1 0.01 99.53 628044N | 1 0.01 99.54 628080J | 1 0.01 99.55 628154Y | 1 0.01 99.56 636703L | 1 0.01 99.57 665991L | 1 0.01 99.58 672549L | 1 0.01 99.59 713467V | 1 0.01 99.60 726116J | 1 0.01 99.61 727092B | 1 0.01 99.62 727098S | 1 0.01 99.63 728148N | 1 0.01 99.64 728259N | 1 0.01 99.65 731697U | 1 0.01 99.66 731927T | 1 0.01 99.67 731957K | 1 0.01 99.68 741100A | 1 0.01 99.69 741659M | 1 0.01 99.70 742112N | 1 0.01 99.71 745933M | 1 0.01 99.72 747743R | 1 0.01 99.73 750817J | 1 0.01 99.74 751680V | 1 0.01 99.75 753048G | 1 0.01 99.76 757159M | 1 0.01 99.77 762259C | 1 0.01 99.78 762297L | 1 0.01 99.79 768160M | 1 0.01 99.80 787787A | 1 0.01 99.81 789013H | 1 0.01 99.82 790824D | 1 0.01 99.83 804300L | 1 0.01 99.84 810871U | 1 0.01 99.85 810933P | 1 0.01 99.86 811010V | 1 0.01 99.87 833642P | 1 0.01 99.88 833789P | 2 0.02 99.90 834012Y | 1 0.01 99.91 853220B | 1 0.01 99.92 853782W | 1 0.01 99.93 877551G | 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