Frequencies for first 10,000 rows of rf_ppoutc variable in natl2013 dataset :

       Poor |
  Pregnancy |
Outcome RFP |
588=f_rf_pp |
        o R |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,318       93.18       93.18
          U |        167        1.67       94.85
          Y |        515        5.15      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 22 Dec 2015