Frequencies for first 10,000 rows of pt variable in namcs2011 dataset :

   Physical |
    therapy |      Freq.     Percent        Cum.
------------+-----------------------------------
         No |      9,791       97.91       97.91
        Yes |        209        2.09      100.00
------------+-----------------------------------
      Total |     10,000      100.00

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