Frequencies for first 10,000 rows of mage15 variable in natl1983 dataset :

     Age of |
     Mother |
  recode 15 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         43        0.43        0.43
          3 |        112        1.12        1.55
          4 |        232        2.32        3.87
          5 |        402        4.02        7.89
          6 |        532        5.32       13.21
          7 |        677        6.77       19.98
          9 |        691        6.91       26.89
         10 |        679        6.79       33.68
         11 |        731        7.31       40.99
         12 |        705        7.05       48.04
         13 |        668        6.68       54.72
         14 |      2,884       28.84       83.56
         15 |      1,213       12.13       95.69
         16 |        371        3.71       99.40
         17 |         60        0.60      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 3 Jan 2016