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

    Roadway |
      Grade |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |         11        0.11        0.11
          1 |      7,396       73.96       74.07
          2 |        753        7.53       81.60
          3 |        110        1.10       82.70
          4 |         16        0.16       82.86
          5 |        528        5.28       88.14
          6 |        630        6.30       94.44
          8 |        430        4.30       98.74
          9 |        126        1.26      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Apr 2016