Imagine, for example, that Germany borrows at a 1% fixed real interest rate with a ten-year maturity and invests the proceeds in repairing domestic transport infrastructure. These investments bring a modest real financial rate of return of 4% through fees, tolls, and, in the longer run, tax revenues (stemming from an increase in GDP).
比如，考虑德国以1%的固定实际利率借入十年期贷款投资于修补国内交通基础设施。这些投资通过通行费、养路费以及长期税收收入（来自GDP的增加）产生4%的温和的实际财务回报率。这些投资将直接强化德国的公共部门资产负债表。这还没有将社会回报（来自交通拥堵情况的减少和空气质量的提高）计算在内。