Frequencies for first 10,000 rows of mage6 variable in natl1980 dataset :

     Age of |
     Mother |
   recode 6 |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      2,118       21.18       21.18
          2 |      3,590       35.90       57.08
          3 |      2,680       26.80       83.88
          4 |      1,207       12.07       95.95
          5 |        339        3.39       99.34
          6 |         66        0.66      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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