Frequencies for ptype variable in parkwork dataset :

  Unit Type |      Freq.     Percent        Cum.
------------+-----------------------------------
          2 |        538       53.69       53.69
          3 |        438       43.71       97.41
          4 |         26        2.59      100.00
------------+-----------------------------------
      Total |      1,002      100.00

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