For example, in the US, the federal budget offsets a substantial part (estimated at 30-40%) of the differences in per capita income levels across states, because poorer states contribute less income tax, on average, and receive higher transfer payments. But this does not imply that these mechanisms also provide insurance against shocks (sudden changes in income for individual states).
比如，在美国，联邦预算打消了各州之间人均收入差异的很大一部分（据估计可达30—40%），因为平均而言，较穷州贡献的所得税较少，而收到的转移支付较多。但这并不意味着这一机制能够提供冲击保险（所谓冲击是指个别州收入的突然变化）。联邦政府的转移支付中有很多与当地商业周期没什么关系，特别是食品券等基本社会支持支付。