Frequencies for first 10,000 rows of exchsum2 variable in namcs2011 dataset :

  Practice exchanges patient |
    clinic summaries through |
       hospital-based system |      Freq.     Percent        Cum.
-----------------------------+-----------------------------------
              Not applicable |      6,555       65.55       65.55
                          No |      2,864       28.64       94.19
                         Yes |        581        5.81      100.00
-----------------------------+-----------------------------------
                       Total |     10,000      100.00

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