Frequencies for first 10,000 rows of leftama variable in nhamcsed2010 dataset :

   Left AMA |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,893       98.93       98.93
        yes |        107        1.07      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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