Frequencies for first 10,000 rows of mage15 variable in natl1976 dataset :

     Age of |
     Mother |
  recode 15 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         81        0.81        0.81
          3 |        193        1.93        2.74
          4 |        356        3.56        6.30
          5 |        603        6.03       12.33
          6 |        660        6.60       18.93
          7 |        761        7.61       26.54
          9 |        773        7.73       34.27
         10 |        742        7.42       41.69
         11 |        692        6.92       48.61
         12 |        679        6.79       55.40
         13 |        608        6.08       61.48
         14 |      2,477       24.77       86.25
         15 |        963        9.63       95.88
         16 |        335        3.35       99.23
         17 |         77        0.77      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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