Frequencies for pmcycl_ds variable in parkwork dataset :

 Motorcycle |
     Engine |
Displacemen |
     t (CC) |      Freq.     Percent        Cum.
------------+-----------------------------------
        599 |          3        0.30        0.30
        649 |          1        0.10        0.40
        745 |          1        0.10        0.50
        999 |          1        0.10        0.60
       1250 |          1        0.10        0.70
       1450 |          1        0.10        0.80
       1500 |          1        0.10        0.90
          . |        993       99.10      100.00
------------+-----------------------------------
      Total |      1,002      100.00

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