Frequencies for measureenddate variable in hqi_op_procedure_volume dataset :

Measure End |
       Date |      Freq.     Percent        Cum.
------------+-----------------------------------
  31dec2012 |      4,136      100.00      100.00
------------+-----------------------------------
      Total |      4,136      100.00

by Jean Roth , jroth@nber.org , 16 Nov 2016