Frequencies for first 10,000 rows of mddo variable in namcs2001 dataset :

    type of |
physician - |
   md or do |      Freq.     Percent        Cum.
------------+-----------------------------------
          1 |      9,319       93.19       93.19
          2 |        681        6.81      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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