Frequencies for first 10,000 rows of combgest variable in natl2016 dataset :

   Combined |
  Gestation |
  -- Detail |
   in Weeks |
 17-47 17th |
    through |
  47th week |
         of |      Freq.     Percent        Cum.
------------+-----------------------------------
         17 |          1        0.01        0.01
         18 |          1        0.01        0.02
         19 |          2        0.02        0.04
         21 |          2        0.02        0.06
         22 |          2        0.02        0.08
         23 |          6        0.06        0.14
         24 |         14        0.14        0.28
         25 |          6        0.06        0.34
         26 |         12        0.12        0.46
         27 |          7        0.07        0.53
         28 |         12        0.12        0.65
         29 |         15        0.15        0.80
         30 |         20        0.20        1.00
         31 |         31        0.31        1.31
         32 |         58        0.58        1.89
         33 |         78        0.78        2.67
         34 |        142        1.42        4.09
         35 |        211        2.11        6.20
         36 |        418        4.18       10.38
         37 |        871        8.71       19.09
         38 |      1,597       15.97       35.06
         39 |      2,635       26.35       61.41
         40 |      2,041       20.41       81.82
         41 |      1,178       11.78       93.60
         42 |        329        3.29       96.89
         43 |        131        1.31       98.20
         44 |         94        0.94       99.14
         45 |         36        0.36       99.50
         46 |         24        0.24       99.74
         47 |         21        0.21       99.95
         99 |          5        0.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 4 Oct 2017