全国经济研究局（National Bureau of Economic Research)是衰退何时开始和结束的正式仲裁。到NBER的网站上（ww

全国经济研究局(National Bureau of Economic Research)是衰退何时开始和结束的正式仲裁。到NBER的网站上(www.nber.org)找到最新的经济周期转折点。它是什么时候开始的？是从膨胀到紧缩，还是倒过来？列出在你一生中所有的衰退(紧缩)，和它们发生的时间与结束的时间。

The official arbiter of when recessions begin and end is the National Bureau of Economic Research, a nonprofit economics research group. Go to the NBER's Web site (www.nber.org) and find the latest turning point in the business cycle. When did it occur？ Was this a switch from expansion to contraction or the other way around？ List all the recessions (contractions) that have occurred during your lifetime and the dates when they began and ended.