The Center for Medicare/Medicaid Services (CMS) is finally revising the methodology on how Physicians (and other Professionals) are reimbursed. Historically, the Medicare Sustainable Growth Rate (SGR) formula determined the annual rates. (SGR is how much an organization can grow without borrowing more money, but for this particular situation, it means the yearly cost to care for each Medicare Beneficiary that does not exceed the GDP).
The past "doc fix" included an annual March 1st update (by congress) of the physician fee schedule based on the actual and expected expenditures (target SGR). After repeated years of debate, negotiation and fluctuation, the "doc fix" and was stopped in 2015 with the "permanent doc fix."