AND WE'VE ONLY JUST BEGUN:

As one example of progress, the report highlights a noticeable decline over the past few years in the hospital readmission rate (that is, the share of discharged patients who are readmitted within 30 days). This decline, the report argues, is probably due, at least partly, to the Partnership for Patients program, a public-private effort involving 3,700 U.S. hospitals to improve the quality of care provided to patients, including after they have been discharged. Declines in readmission rates have been larger at hospitals that are part of this partnership than at other hospitals.

What are the consequences if the slower growth continues? Official projections, which do not fully incorporate the recent slowdown, suggest that spending on Medicare will rise from 3.7 percent of gross domestic product in 2011 to 6.7 percent in 2085. In contrast, the Economic Report of the President shows in an illustrative calculation that it will rise only to 3.8 percent of GDP by 2085 -- not much higher than it is today -- if the per-beneficiary growth rate we have seen in the past five years keeps going.

If this happens, in other words, a major part of our long- term budget problem would disappear. And the nation's long-term fiscal gap would narrow by almost a third, according to a recent study by the economists William Gale of the Brookings Institution and Alan Auerbach of the University of California at Berkeley.

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