Frequencies for first 10,000 rows of combgest variable in natlterr2015 dataset :

   Combined |
  Gestation |
  -- Detail |
   in Weeks |
 17-47 17th |
    through |
  47th week |
         of |      Freq.     Percent        Cum.
------------+-----------------------------------
         19 |          2        0.02        0.02
         20 |          1        0.01        0.03
         21 |          1        0.01        0.04
         22 |          3        0.03        0.07
         23 |         10        0.10        0.17
         24 |          7        0.07        0.24
         25 |         10        0.10        0.34
         26 |         15        0.15        0.49
         27 |         17        0.17        0.66
         28 |         22        0.22        0.88
         29 |         24        0.24        1.12
         30 |         36        0.36        1.48
         31 |         55        0.55        2.03
         32 |         66        0.66        2.69
         33 |        125        1.25        3.94
         34 |        173        1.73        5.67
         35 |        266        2.66        8.33
         36 |        409        4.09       12.42
         37 |        910        9.10       21.52
         38 |      1,649       16.49       38.01
         39 |      2,239       22.39       60.40
         40 |      1,515       15.15       75.55
         41 |        659        6.59       82.14
         42 |        277        2.77       84.91
         43 |        166        1.66       86.57
         44 |        120        1.20       87.77
         45 |         43        0.43       88.20
         46 |         38        0.38       88.58
         47 |         32        0.32       88.90
         99 |      1,110       11.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 20 Oct 2016