Frequencies for first 10,000 rows of vprofile variable in vehicle dataset :

    roadway |
      grade |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         72        0.72        0.72
          1 |      5,896       58.96       59.68
          2 |        285        2.85       62.53
          3 |        118        1.18       63.71
          4 |         29        0.29       64.00
          5 |        637        6.37       70.37
          6 |        834        8.34       78.71
          8 |      2,027       20.27       98.98
          9 |        102        1.02      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Oct 2016