在危机前的二十年中，美国经济中生产国际可贸易商品和服务（占总产出的三分之一）的部门没有增加任何就业岗位，即使用增加值衡量，其增长比不可贸易部门更快。
In the two decades that preceded the crisis, the sector of the US economy that produces internationally tradable goods and services – one-third of overall output – failed to generate any increase in jobs, even though it was growing faster than the non-tradable sector in terms of value added.