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

 Do you refer any |
 of your patients |
    to a provider |
  outside of your |
 office or group? |      Freq.     Percent        Cum.
------------------+-----------------------------------
            Blank |         15        0.15        0.15
          Unknown |          1        0.01        0.16
              Yes |      9,556       95.56       95.72
               No |        428        4.28      100.00
------------------+-----------------------------------
            Total |     10,000      100.00

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