Frequencies for pwgtcd_tr variable in parkwork dataset :

      Truck |
     Weight |
     Rating |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         97        9.68        9.68
          2 |        147       14.67       24.35
          3 |         15        1.50       25.85
          4 |          8        0.80       26.65
          5 |          7        0.70       27.35
          6 |         24        2.40       29.74
          7 |         14        1.40       31.14
          8 |         93        9.28       40.42
          . |        597       59.58      100.00
------------+-----------------------------------
      Total |      1,002      100.00

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