Frequencies for rownumber variable in busrules2015 dataset :

 Row Number |      Freq.     Percent        Cum.
------------+-----------------------------------
         10 |      8,177       81.00       81.00
         11 |        766        7.59       88.59
         12 |        352        3.49       92.08
         13 |        183        1.81       93.89
         14 |        151        1.50       95.38
         15 |         82        0.81       96.20
         16 |         74        0.73       96.93
         17 |         52        0.52       97.44
         18 |         54        0.53       97.98
         19 |         38        0.38       98.36
         20 |         27        0.27       98.62
         21 |         32        0.32       98.94
         22 |         27        0.27       99.21
         23 |         25        0.25       99.46
         24 |         25        0.25       99.70
         25 |          8        0.08       99.78
         26 |          7        0.07       99.85
         27 |          2        0.02       99.87
         28 |          2        0.02       99.89
         29 |          2        0.02       99.91
         30 |          2        0.02       99.93
         31 |          2        0.02       99.95
         32 |          3        0.03       99.98
         33 |          1        0.01       99.99
         34 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,095      100.00

by Jean Roth , jroth@nber.org , 9 Dec 2017