Frequencies for first 10,000 rows of mage12 variable in natlterr2000 dataset :

     Age of |
     Mother |
  recode 12 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         49        0.49        0.49
          3 |        137        1.37        1.86
          4 |        265        2.65        4.51
          5 |        392        3.92        8.43
          6 |        535        5.35       13.78
          7 |        597        5.97       19.75
          8 |      3,240       32.40       52.15
          9 |      2,569       25.69       77.84
         10 |      1,447       14.47       92.31
         11 |        627        6.27       98.58
         12 |        132        1.32       99.90
         13 |         10        0.10      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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