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

 Percent of patient care revenue |
       from usual, customary and |
          reasonable fee-for-ser |      Freq.     Percent        Cum.
---------------------------------+-----------------------------------
                           Blank |      1,232       12.32       12.32
Less than or equal to 25 percent |      2,363       23.63       35.95
                   26-50 percent |      1,246       12.46       48.41
                   51-75 percent |        834        8.34       56.75
            More than 75 percent |      4,325       43.25      100.00
---------------------------------+-----------------------------------
                           Total |     10,000      100.00

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