Frequencies for first 10,000 rows of pt variable in namcs2013 dataset :

   Physical |
    therapy |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,795       97.95       97.95
        Yes |        205        2.05      100.00
------------+-----------------------------------
      Total |     10,000      100.00

by Jean Roth , jroth@nber.org , 27 Mar 2017