Frequencies for first 10,000 rows of pregtest variable in nhamcsed2011 dataset :

Pregnancy/H |
    CG test |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,373       93.73       93.73
        Yes |        627        6.27      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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