Frequencies for first 10,000 rows of refsocs variable in nhamcsed2007 dataset :

   refer to |
     social |
   services |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      9,851       98.51       98.51
        yes |        149        1.49      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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