Frequencies for first 10,000 rows of exercise variable in namcs2005 dataset :

   exercise |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      8,716       87.16       87.16
          1 |      1,284       12.84      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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