Frequencies for first 10,000 rows of estgest variable in natlterr2006 dataset :

Obstetric/C |
    linical |
  Gestation |
   Est. RFP |
573=f_cline |
     st U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
         17 |          1        0.01        0.01
         18 |          1        0.01        0.02
         20 |          4        0.04        0.06
         21 |          5        0.05        0.11
         22 |          4        0.04        0.15
         23 |          5        0.05        0.20
         24 |          7        0.07        0.27
         25 |          7        0.07        0.34
         26 |          4        0.04        0.38
         27 |          5        0.05        0.43
         28 |         19        0.19        0.62
         29 |         25        0.25        0.87
         30 |         32        0.32        1.19
         31 |         31        0.31        1.50
         32 |         53        0.53        2.03
         33 |         62        0.62        2.65
         34 |        130        1.30        3.95
         35 |        273        2.73        6.68
         36 |        527        5.27       11.95
         37 |      1,210       12.10       24.05
         38 |      1,963       19.63       43.68
         39 |      2,137       21.37       65.05
         40 |      1,415       14.15       79.20
         41 |        494        4.94       84.14
         42 |         80        0.80       84.94
         43 |         25        0.25       85.19
         44 |          8        0.08       85.27
         45 |          2        0.02       85.29
         47 |          2        0.02       85.31
         99 |      1,469       14.69      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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