Frequencies for first 10,000 rows of gestat10 variable in natl1999 dataset :

  Gestation |
  Recode 10 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          3        0.03        0.03
          2 |         95        0.95        0.98
          3 |        182        1.82        2.80
          4 |        658        6.58        9.38
          5 |        483        4.83       14.21
          6 |      4,895       48.95       63.16
          7 |      1,885       18.85       82.01
          8 |        962        9.62       91.63
          9 |        827        8.27       99.90
         10 |         10        0.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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