Frequencies for first 10,000 rows of physasst variable in nhamcsopd1997 dataset :

  physician |
  assistant |
       seen |      Freq.     Percent        Cum.
------------+-----------------------------------
          0 |      9,835       98.35       98.35
          1 |        165        1.65      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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