Frequencies for first 10,000 rows of mage12 variable in natl2000 dataset :

     Age of |
     Mother |
  recode 12 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         38        0.38        0.38
          3 |         90        0.90        1.28
          4 |        179        1.79        3.07
          5 |        312        3.12        6.19
          6 |        431        4.31       10.50
          7 |        582        5.82       16.32
          8 |      3,114       31.14       47.46
          9 |      2,745       27.45       74.91
         10 |      1,631       16.31       91.22
         11 |        729        7.29       98.51
         12 |        142        1.42       99.93
         13 |          7        0.07      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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