Here's the pertinent paragraph in the Medicare document I found:
Section 1848(f) of the Act, as amended by section 4503 of the Balanced Budget Act of 1997 (BBA) (Pub. L. 105-33), enacted on August 5, 1997, replaced the Medicare Volume Performance Standard (MVPS) with a Sustainable Growth Rate (SGR) provision. Section 1848(f)(2) of the Act specifies the formula for establishing yearly SGR targets for physicians' services under Medicare. The use of SGR targets is intended to control the growth in aggregate Medicare expenditures for physicians' services.
google SGR or Sustainable Growth Rate.
The 21% reduction is the result of the calculation for 2010.
Just curious...you said "And yet, about half their costs are administrative". So the percentage of premium I send to Harvard Pilgrim that reimburses doctors and providers is 50%?
Harvard Pilgrims most recent report is 10.10% administrative expense, Medical expense 88.4% (reimbursement), Income 2.55% (profit)