Frequencies for first 10,000 rows of mager variable in natl2009 dataset :

   Mother's |
Single Year |
 of Age U;R |      Freq.     Percent        Cum.
------------+-----------------------------------
         13 |          5        0.05        0.05
         14 |         15        0.15        0.20
         15 |         49        0.49        0.69
         16 |        112        1.12        1.81
         17 |        207        2.07        3.88
         18 |        359        3.59        7.47
         19 |        500        5.00       12.47
         20 |        554        5.54       18.01
         21 |        596        5.96       23.97
         22 |        612        6.12       30.09
         23 |        556        5.56       35.65
         24 |        569        5.69       41.34
         25 |        603        6.03       47.37
         26 |        605        6.05       53.42
         27 |        629        6.29       59.71
         28 |        584        5.84       65.55
         29 |        529        5.29       70.84
         30 |        493        4.93       75.77
         31 |        414        4.14       79.91
         32 |        393        3.93       83.84
         33 |        306        3.06       86.90
         34 |        296        2.96       89.86
         35 |        271        2.71       92.57
         36 |        177        1.77       94.34
         37 |        162        1.62       95.96
         38 |        121        1.21       97.17
         39 |         92        0.92       98.09
         40 |         75        0.75       98.84
         41 |         34        0.34       99.18
         42 |         39        0.39       99.57
         43 |         17        0.17       99.74
         44 |         13        0.13       99.87
         45 |          6        0.06       99.93
         46 |          1        0.01       99.94
         47 |          4        0.04       99.98
         48 |          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