Frequencies for first 10,000 rows of revcaser variable in namcs2009 dataset :

 percent of patient care revenue |
                 from case rates |      Freq.     Percent        Cum.
---------------------------------+-----------------------------------
                           blank |        924        9.24        9.24
less than or equal to 25 percent |      9,012       90.12       99.36
                   51-75 percent |         22        0.22       99.58
            more than 75 percent |         42        0.42      100.00
---------------------------------+-----------------------------------
                           Total |     10,000      100.00

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