Frequencies for first 10,000 rows of speccat variable in namcs2006 dataset :

    physician specialty |
  recoded into 3 groups |      Freq.     Percent        Cum.
------------------------+-----------------------------------
 primary care specialty |      8,662       86.62       86.62
surgical care specialty |        887        8.87       95.49
 medical care specialty |        451        4.51      100.00
------------------------+-----------------------------------
                  Total |     10,000      100.00

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