Frequencies for chainzip variable in hcris2552_96_2003 dataset :

   chainzip |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      6,188       99.92       99.92
      45202 |          1        0.02       99.94
      49048 |          1        0.02       99.95
      70809 |          1        0.02       99.97
      77080 |          1        0.02       99.98
      95128 |          1        0.02      100.00
------------+-----------------------------------
      Total |      6,193      100.00

by Jean Roth , jroth@nber.org , 8 Sep 2018