NOTE TO READERS: In April 2014, Medicare released 2012 billing data that suppressed payments to medical providers for services they rendered to small numbers of patients. Medicare has since revised its methodology to include additional payments made to providers, and re-released 2012 billing data in June 2015. For this reason, the total payment figures cited in stories published prior to June 2015 may differ from figures cited from June 2015 onward. The original data released can be seen here, and updated figures for 2012, along with 2013 billing data, can be seen here.

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