Frequencies for first 10,000 rows of cervcx variable in nhamcsed2001 dataset :

cervical/ur |
     ethral |
    culture |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,923       99.23       99.23
          1 |         77        0.77      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016