Frequencies for first 10,000 rows of gestat10 variable in natl2001 dataset :

  Gestation |
  Recode 10 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          3        0.03        0.03
          2 |         91        0.91        0.94
          3 |        152        1.52        2.46
          4 |        702        7.02        9.48
          5 |        541        5.41       14.89
          6 |      5,350       53.50       68.39
          7 |      1,670       16.70       85.09
          8 |        751        7.51       92.60
          9 |        727        7.27       99.87
         10 |         13        0.13      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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