Frequencies for first 10,000 rows of mage7 variable in natl1976 dataset :

     Age of |
     Mother |
   recode 7 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |         81        0.81        0.81
          2 |      2,573       25.73       26.54
          3 |      3,494       34.94       61.48
          4 |      2,477       24.77       86.25
          5 |        963        9.63       95.88
          6 |        335        3.35       99.23
          7 |         77        0.77      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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