Frequencies for first 10,000 rows of sex variable in demo2004q4 dataset :

   Code for |
  patient's |
        sex |      Freq.     Percent        Cum.
------------+-----------------------------------
            |        653        6.53        6.53
          F |      5,127       51.27       57.80
          M |      4,090       40.90       98.70
         NS |          5        0.05       98.75
        UNK |        125        1.25      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 18 Dec 2015