Frequencies for first 10,000 rows of rf_ppoutc variable in natlterr2008 dataset :

       Poor |
  Pregnancy |
Outcome RFP |
588=f_rf_pp |
        o R |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      6,061       60.61       60.61
          N |      3,919       39.19       99.80
          Y |         20        0.20      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 May 2016