Frequencies for first 10,000 rows of rail variable in accident dataset : Rail Grade | Xing ID | Freq. Percent Cum. ------------+----------------------------------- 0000000 | 9,907 99.07 99.07 003460M | 1 0.01 99.08 003638J | 1 0.01 99.09 003733E | 1 0.01 99.10 025448S | 1 0.01 99.11 026503T | 1 0.01 99.12 026588X | 1 0.01 99.13 026640A | 1 0.01 99.14 027358A | 1 0.01 99.15 027571X | 1 0.01 99.16 028326X | 1 0.01 99.17 028706E | 1 0.01 99.18 028971U | 1 0.01 99.19 029091T | 1 0.01 99.20 029184M | 1 0.01 99.21 029677A | 1 0.01 99.22 253125Y | 1 0.01 99.23 253320Y | 1 0.01 99.24 272332U | 1 0.01 99.25 272462R | 1 0.01 99.26 272544X | 1 0.01 99.27 330474V | 1 0.01 99.28 339729V | 1 0.01 99.29 339927R | 1 0.01 99.30 346987S | 1 0.01 99.31 351427V | 1 0.01 99.32 352244F | 1 0.01 99.33 352830A | 1 0.01 99.34 425330G | 1 0.01 99.35 425535A | 1 0.01 99.36 425953R | 1 0.01 99.37 426051P | 1 0.01 99.38 434196W | 1 0.01 99.39 434249T | 1 0.01 99.40 434306E | 1 0.01 99.41 434385T | 1 0.01 99.42 434525T | 1 0.01 99.43 434601J | 1 0.01 99.44 437625H | 1 0.01 99.45 438168G | 1 0.01 99.46 500540B | 1 0.01 99.47 500741S | 1 0.01 99.48 516109U | 1 0.01 99.49 600615D | 1 0.01 99.50 621378X | 1 0.01 99.51 622309T | 1 0.01 99.52 622311U | 1 0.01 99.53 622337W | 1 0.01 99.54 622915Y | 1 0.01 99.55 622952B | 1 0.01 99.56 624767A | 1 0.01 99.57 625048F | 1 0.01 99.58 625301Y | 1 0.01 99.59 625897H | 1 0.01 99.60 627450G | 1 0.01 99.61 628045V | 1 0.01 99.62 628154Y | 1 0.01 99.63 661952G | 1 0.01 99.64 728314L | 1 0.01 99.65 741397H | 1 0.01 99.66 745904C | 1 0.01 99.67 746795E | 1 0.01 99.68 746883P | 1 0.01 99.69 746896R | 1 0.01 99.70 746905M | 1 0.01 99.71 747711K | 1 0.01 99.72 747871Y | 1 0.01 99.73 748121S | 1 0.01 99.74 749238D | 1 0.01 99.75 749954U | 1 0.01 99.76 750394L | 1 0.01 99.77 750755N | 1 0.01 99.78 751653Y | 1 0.01 99.79 752753G | 2 0.02 99.81 760488P | 1 0.01 99.82 760607W | 1 0.01 99.83 760687S | 1 0.01 99.84 761424G | 1 0.01 99.85 761584V | 1 0.01 99.86 787633P | 1 0.01 99.87 787792W | 1 0.01 99.88 787819D | 1 0.01 99.89 804375K | 1 0.01 99.90 804595F | 1 0.01 99.91 810867E | 1 0.01 99.92 847225T | 1 0.01 99.93 853231N | 1 0.01 99.94 868255W | 1 0.01 99.95 868370D | 1 0.01 99.96 868405C | 1 0.01 99.97 9999999 | 3 0.03 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 18 Apr 2016