Frequencies for pbus_use variable in parkwork dataset :

    bus use |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      1,143       99.74       99.74
          5 |          2        0.17       99.91
         98 |          1        0.09      100.00
------------+-----------------------------------
      Total |      1,146      100.00

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