Frequencies for pbszone variable in pbtype dataset :

school zone |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      6,017       96.23       96.23
          1 |         50        0.80       97.03
          9 |        186        2.97      100.00
------------+-----------------------------------
      Total |      6,253      100.00

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