Frequencies for first 10,000 rows of gestrec10 variable in natlterr2011 dataset :

  Gestation |
  Recode 10 |
        U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |          6        0.06        0.06
          2 |         79        0.79        0.85
          3 |        125        1.25        2.10
          4 |        165        1.65        3.75
          5 |        945        9.45       13.20
          6 |      3,087       30.87       44.07
          7 |      2,148       21.48       65.55
          8 |      1,310       13.10       78.65
          9 |        479        4.79       83.44
         10 |        363        3.63       87.07
         99 |      1,293       12.93      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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