Frequencies for first 10,000 rows of rail variable in accident dataset : rail grade | crossing | identifier | Freq. Percent Cum. ------------+----------------------------------- 0000000 | 9,957 99.57 99.57 028601R | 1 0.01 99.58 063001L | 1 0.01 99.59 245010J | 1 0.01 99.60 272517B | 1 0.01 99.61 279613C | 1 0.01 99.62 290486C | 1 0.01 99.63 296169T | 1 0.01 99.64 330483U | 1 0.01 99.65 352245M | 1 0.01 99.66 386440H | 1 0.01 99.67 426260X | 1 0.01 99.68 441373R | 1 0.01 99.69 480072B | 1 0.01 99.70 543266J | 1 0.01 99.71 546495N | 1 0.01 99.72 608939D | 1 0.01 99.73 621029M | 1 0.01 99.74 622304J | 1 0.01 99.75 624300N | 1 0.01 99.76 628116P | 1 0.01 99.77 628160C | 1 0.01 99.78 628183J | 1 0.01 99.79 628320N | 1 0.01 99.80 635885w | 1 0.01 99.81 719080L | 1 0.01 99.82 723354S | 1 0.01 99.83 724755V | 1 0.01 99.84 725277B | 1 0.01 99.85 725396K | 1 0.01 99.86 725433K | 1 0.01 99.87 725701T | 1 0.01 99.88 726128D | 1 0.01 99.89 727029M | 1 0.01 99.90 727596B | 1 0.01 99.91 727726V | 1 0.01 99.92 728232R | 1 0.01 99.93 729038P | 1 0.01 99.94 745855H | 1 0.01 99.95 746784S | 1 0.01 99.96 752752A | 1 0.01 99.97 753260X | 1 0.01 99.98 811635T | 1 0.01 99.99 926249D | 1 0.01 100.00 ------------+----------------------------------- Total | 10,000 100.00 by Jean Roth , jroth@nber.org , 22 Oct 2016