Frequencies for first 10,000 rows of gest_imp variable in natl2009 dataset :

  Gestation |
    Imputed |
   Flag U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      1,002       10.02       10.02
          . |      8,998       89.98      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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