The aging of the US population undoubtedly will be associated with macroeconomic changes. In particular, some combination of lower consumption growth and increased labor input will ultimately be required. But, the timing of these changes can have important effects on variables like the rate of return to capital and wages. If the adjustment to consumption is slow, which would be the case if budget deficits were allowed to rise significantly as the population ages, then aging is likely to be associated with an increase in the return to capital and a reduction in wages.

This paper examines the generational aspect of the current Medicare system and some stylized reforms. We find that the rates of return on Medicare for today's workers are higher than those for Social Security and that the Medicare system is shifting a greater share of the burden on future workers than is Social Security. Nonetheless, the rates of return on Medicare, using the Medicare Trustees assumptions, are still not that high--roughly 2 percent for today's youngest workers. But forecasting future Medicare expenditures is quite difficult. Under an alternative higher-cost baseline, which we consider plausible, rates of return for today's youngest workers will exceed 3 percent. Putting Medicare on a sustainable basis by raising the payroll tax or reducing benefits would greatly reduce the rate of return for today's workers. Under the Trustees assumptions, for example, the payroll tax would have to be increased by 2.0 percent of payroll to put the Medicare system in balance in perpetuity. This policy would reduce the rate of return on today's youngest workers to about 1.3 percent.

There is a great deal of geographic variation in Medicare spending. For example, while the average Medicare cost per beneficiary was around $5200 in 1996, Medicare spending, adjusted for diffences in regional prices and demographic composition, was about $8000 per person in Miami, but only $3500 in Minneapolis. In this paper, we explore the source of this variation. We find that a substantial amount can be explained by differences across areas in the health of the elderly population. This finding suggests that some of the geographic variation in Medicare spending is efficient. But even accounting for differences in the health of the population, significant variation remains. We have been able to explain some of the remaining variation. The strongest factors are supply variables: for-profit hospitals and specialist physicians both increase Medicare spending. If these factors are exogenous, public policy may want to consider the supply of medical services more than it currently does. We do not find that expensive places spend a disproportionate amount on those near death.