Frequencies for first 10,000 rows of rf_gest variable in linkpe2009psden dataset :

Gestational |
 Diabetes R |
(f_rf_gdiab |
  rep flag) |      Freq.     Percent        Cum.
------------+-----------------------------------
            |      3,422       34.22       34.22
          N |      6,435       64.35       98.57
          U |          1        0.01       98.58
          Y |        142        1.42      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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