Frequencies for first 10,000 rows of prmcarer variable in namcs2008 dataset :

 percent of patient care revenue |
                   from medicare |      Freq.     Percent        Cum.
---------------------------------+-----------------------------------
                           blank |        412        4.12        4.12
less than or equal to 25 percent |      5,974       59.74       63.86
                   26-50 percent |      2,629       26.29       90.15
                   51-75 percent |        889        8.89       99.04
            more than 75 percent |         96        0.96      100.00
---------------------------------+-----------------------------------
                           Total |     10,000      100.00

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