In normal times, deficits crowd out private investment (and perhaps crowd in private saving and/or foreign capital), and hence reduce future growth. By contrast, in a deep, long-lasting recession, with the central bank’s policy rate at the zero lower bound (ZLB), a well-timed, sensible fiscal response can, in principle, be helpful.
大量赤字通常是不受欢迎的，但有时赤字可以是良性甚至受欢迎的，比如在衰退、战争期间或是被用于为生产性公共投资融资时。在正常时期，赤字会挤出私人投资（也可能挤入私人储蓄和/或外国资本），从而抑制未来增长。相反，在深度、长期的衰退中，在央行政策利率处于零下限（zero lower bound，ZLB）时，理论上时机恰当的合适财政反应将是有所裨益的。