Frequencies for first 10,000 rows of attphys variable in nhamcsed2006 dataset :

         ed |
  attending |
  physician |
       seen |      Freq.     Percent        Cum.
------------+-----------------------------------
         no |      1,300       13.00       13.00
        yes |      8,700       87.00      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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