Frequencies for pem_use variable in parkwork dataset :

  Emergency |
        Use |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      1,055       99.15       99.15
          1 |          3        0.28       99.44
          8 |          4        0.38       99.81
          9 |          2        0.19      100.00
------------+-----------------------------------
      Total |      1,064      100.00

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