Frequencies for pmcycl_ds variable in parkwork dataset :

 motorcycle |
     engine |
displacemen |
     t (cc) |      Freq.     Percent        Cum.
------------+-----------------------------------
        805 |          1        0.09        0.09
       1202 |          1        0.09        0.18
       1450 |          1        0.09        0.27
       1500 |          1        0.09        0.37
       1584 |          1        0.09        0.46
       1800 |          1        0.09        0.55
          . |      1,085       99.45      100.00
------------+-----------------------------------
      Total |      1,091      100.00

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