Frequencies for first 10,000 rows of mager variable in natlterr2013 dataset :

   Mother's |
Single Year |
 of Age U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
         13 |          1        0.01        0.01
         14 |         13        0.13        0.14
         15 |         58        0.58        0.72
         16 |        131        1.31        2.03
         17 |        231        2.31        4.34
         18 |        369        3.69        8.03
         19 |        493        4.93       12.96
         20 |        592        5.92       18.88
         21 |        635        6.35       25.23
         22 |        585        5.85       31.08
         23 |        619        6.19       37.27
         24 |        534        5.34       42.61
         25 |        575        5.75       48.36
         26 |        522        5.22       53.58
         27 |        495        4.95       58.53
         28 |        489        4.89       63.42
         29 |        442        4.42       67.84
         30 |        464        4.64       72.48
         31 |        418        4.18       76.66
         32 |        421        4.21       80.87
         33 |        343        3.43       84.30
         34 |        301        3.01       87.31
         35 |        281        2.81       90.12
         36 |        215        2.15       92.27
         37 |        201        2.01       94.28
         38 |        166        1.66       95.94
         39 |        129        1.29       97.23
         40 |         98        0.98       98.21
         41 |         83        0.83       99.04
         42 |         47        0.47       99.51
         43 |         26        0.26       99.77
         44 |         13        0.13       99.90
         45 |          4        0.04       99.94
         46 |          3        0.03       99.97
         47 |          2        0.02       99.99
         48 |          1        0.01      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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