Crowding Out in Ricardian Economies

The crowding-out coefficient is the ratio of the reduction in privately-issued bonds to the increase in government bonds that are issued to finance a tax cut. If (1) Ricardian equivalence holds, and (2) households do not simultaneously borrow risklessly and have positive gross positions in other riskless assets, the crowding-out coefficient equals the fraction of the aggregate tax cut that accrues to households that borrow. In the conventional case in which all households receive equal tax cuts, the crowding-out coefficient equals the fraction of households that borrow. In the United States, about 75% of households borrow, so the crowding-out coefficient is predicted to be 0.75, which differs from econometric estimates that are around 0.5. I explore extensions of the model, such as a departure from Ricardian Equivalence or the introduction of cross-sectional variation in taxes, that might account for this difference