Changes in fiscal policy typically entail two kinds of lags: the legislative lag--between when legislation is proposed and when it is signed into law--and the implementation lag--from when a new fiscal law is enacted and when it takes effect. These lags imply that substantial time evolves...

We develop a rational expectations framework to study the consequences of alternative means to resolve the "unfunded liabilities'' problem---unsustainable exponential growth in federal Social Security, Medicare, and Medicaid spending with no plan to finance it. Resolution requires specifying a...