Frequencies for first 10,000 rows of estgest variable in natlterr2010 dataset :

Obstetric/C |
    linical |
  Gestation |
   Est. RFP |
573=f_cline |
     st U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
          3 |          1        0.01        0.01
         10 |          1        0.01        0.02
         15 |          1        0.01        0.03
         17 |          1        0.01        0.04
         20 |          4        0.04        0.08
         22 |          4        0.04        0.12
         23 |          6        0.06        0.18
         24 |          4        0.04        0.22
         25 |          9        0.09        0.31
         26 |          8        0.08        0.39
         27 |         12        0.12        0.51
         28 |         18        0.18        0.69
         29 |         14        0.14        0.83
         30 |         28        0.28        1.11
         31 |         40        0.40        1.51
         32 |         53        0.53        2.04
         33 |         68        0.68        2.72
         34 |        117        1.17        3.89
         35 |        218        2.18        6.07
         36 |        479        4.79       10.86
         37 |      1,204       12.04       22.90
         38 |      2,160       21.60       44.50
         39 |      2,265       22.65       67.15
         40 |      1,365       13.65       80.80
         41 |        487        4.87       85.67
         42 |         90        0.90       86.57
         43 |         28        0.28       86.85
         44 |          3        0.03       86.88
         45 |          1        0.01       86.89
         91 |          1        0.01       86.90
         99 |      1,310       13.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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