Though policy alternates between supply-side and neo-Keynesian enthusiasm, the one persistent reality is a significant decline of investment as a share of national income in most high-income countries in recent years. According to IMF data, gross investment spending in these countries has declined from 24.9% of GDP in 1990 to just 20% in 2013.
尽管政策在供给学派和新凯恩斯主义狂热之间摇摆，但一个持久的现实是近几年来大部分高收入国家投资占国民收入的比重大幅下降。根据IMF的数据，这些国家的总投资支出占GDP之比从1990年的24.9%下降到2013年的20%。