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

   Mother's |
Single Year |
 of Age U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
         12 |          2        0.02        0.02
         13 |          2        0.02        0.04
         14 |         28        0.28        0.32
         15 |         68        0.68        1.00
         16 |        173        1.73        2.73
         17 |        254        2.54        5.27
         18 |        369        3.69        8.96
         19 |        458        4.58       13.54
         20 |        531        5.31       18.85
         21 |        509        5.09       23.94
         22 |        583        5.83       29.77
         23 |        574        5.74       35.51
         24 |        574        5.74       41.25
         25 |        575        5.75       47.00
         26 |        569        5.69       52.69
         27 |        529        5.29       57.98
         28 |        527        5.27       63.25
         29 |        434        4.34       67.59
         30 |        417        4.17       71.76
         31 |        394        3.94       75.70
         32 |        406        4.06       79.76
         33 |        362        3.62       83.38
         34 |        342        3.42       86.80
         35 |        307        3.07       89.87
         36 |        257        2.57       92.44
         37 |        191        1.91       94.35
         38 |        164        1.64       95.99
         39 |        125        1.25       97.24
         40 |        115        1.15       98.39
         41 |         59        0.59       98.98
         42 |         40        0.40       99.38
         43 |         33        0.33       99.71
         44 |         12        0.12       99.83
         45 |         10        0.10       99.93
         46 |          2        0.02       99.95
         48 |          4        0.04       99.99
         50 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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