Frequencies for first 10,000 rows of rf_phype variable in natl2014 dataset :

Pre-pregnan |
         cy |
Hypertensio |
    n Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,613       96.13       96.13
          U |        128        1.28       97.41
          Y |        259        2.59      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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