Frequencies for first 10,000 rows of ip_chlam variable in natlterr2014 dataset 

Chlamydia Y |
        Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      1,077       10.77       10.77
          N |      8,640       86.40       97.17
          U |        127        1.27       98.44
          Y |        156        1.56      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 15 Jun 2016