Frequencies for first 10,000 rows of rf_pdiab variable in natl2015 dataset :

Pre-pregnan |
cy Diabetes |
      Y Yes |      Freq.     Percent        Cum.
------------+-----------------------------------
          N |      9,806       98.06       98.06
          U |        108        1.08       99.14
          Y |         86        0.86      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Oct 2016