Frequencies for first 10,000 rows of gestat3 variable in natl1978 dataset :

  Gestation |
   Recode 3 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |        862        8.62        8.62
          2 |      7,137       71.37       79.99
          3 |      2,001       20.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016