In this study, we present new evidence that the postwar U.S. federal budget deficit was explosive in nature. Because of the government's inevitable attempts to reduce high or rapidly growing budget deficits, the deficit may contain a substantial component that periodically collapses, which...

We show, in this study, that the U.S. public debt–GDP ratio was explosive in nature during the 1791–2009 sample period. The huge increase in U.S. debt during World War II is responsible for this result. Our findings differ profoundly from those generated by the standard unit root tests,...