Frequencies for first 10,000 rows of sex variable in demo2007q2 dataset :

   Code for |
  patient's |
        sex |      Freq.     Percent        Cum.
------------+-----------------------------------
            |        618        6.18        6.18
          F |      5,280       52.80       58.98
          M |      4,076       40.76       99.74
         NS |         19        0.19       99.93
        UNK |          7        0.07      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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