这个的背景是从20世纪60年代到21世纪初，美国的平均健康指数上升了。

The background to this is that from the 1960s into the early 2000s, measures of average wellbeing went up in the US.

youdao

当天道琼斯指数上升了86点。

The Dow Jones index rose by 86 points on the day.

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过去12个月中，美国的消费者价格指数上升了2.1%。

Over the past 12 months, the consumer-price index has risen 2.1%.

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Now, it's also the case that this is fundamentally what class this algorithm falls into, it is going to take exponential amount of time.

哪个种类的一个实例,这个问题的时间复杂度是指数级的，也就是当n上升的时候。

麻省理工公开课 - 计算机科学及编程导论课程节选