Frequencies for first 10,000 rows of ager variable in nhamcsopd2011 dataset :

       Age recode |      Freq.     Percent        Cum.
------------------+-----------------------------------
   Under 15 years |      1,870       18.70       18.70
      15-24 years |      1,170       11.70       30.40
      25-44 years |      2,613       26.13       56.53
      45-64 years |      2,941       29.41       85.94
      65-74 years |        781        7.81       93.75
75 years and over |        625        6.25      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 28 Mar 2016