Frequencies for first 10,000 rows of mental variable in nhamcsopd1996 dataset :

     mental |
     status |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,670       96.70       96.70
          1 |        330        3.30      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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