Frequencies for psp_use variable in parkwork dataset :

Special Use |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |        993       99.10       99.10
          1 |          2        0.20       99.30
          5 |          3        0.30       99.60
          6 |          2        0.20       99.80
          7 |          1        0.10       99.90
          8 |          1        0.10      100.00
------------+-----------------------------------
      Total |      1,002      100.00

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