Frequencies for first 10,000 rows of pt variable in namcs2012 dataset :

   Physical |
    therapy |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,821       98.21       98.21
        Yes |        179        1.79      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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