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

   Mother's |
Single Year |
 of Age U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
         12 |          1        0.01        0.01
         13 |          5        0.05        0.06
         14 |         16        0.16        0.22
         15 |         77        0.77        0.99
         16 |        156        1.56        2.55
         17 |        268        2.68        5.23
         18 |        412        4.12        9.35
         19 |        507        5.07       14.42
         20 |        571        5.71       20.13
         21 |        571        5.71       25.84
         22 |        566        5.66       31.50
         23 |        562        5.62       37.12
         24 |        528        5.28       42.40
         25 |        561        5.61       48.01
         26 |        533        5.33       53.34
         27 |        511        5.11       58.45
         28 |        477        4.77       63.22
         29 |        456        4.56       67.78
         30 |        459        4.59       72.37
         31 |        422        4.22       76.59
         32 |        408        4.08       80.67
         33 |        342        3.42       84.09
         34 |        287        2.87       86.96
         35 |        302        3.02       89.98
         36 |        258        2.58       92.56
         37 |        201        2.01       94.57
         38 |        161        1.61       96.18
         39 |        125        1.25       97.43
         40 |         86        0.86       98.29
         41 |         73        0.73       99.02
         42 |         40        0.40       99.42
         43 |         29        0.29       99.71
         44 |         14        0.14       99.85
         45 |          6        0.06       99.91
         46 |          3        0.03       99.94
         47 |          4        0.04       99.98
         49 |          1        0.01       99.99
         50 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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