https://personal.vanguard.com/us/insights/video/VP-innovation-economic-
growth-11302010
先声明，我觉得这算是忽悠，brokerage trying to persuade people to keep
investing so they get to earn commissions and fees. and they didn't show
innovations during the good times or the % of innovations by good/bad times.
但是，首先，我是科学和进步的坚定信徒，看这么个小片子让我特高兴。其次，右上角
，S&P 500 里，在危机时成立的公司的比重越来越大；还是个挺有意思的现象，也许只
说明工作不好找的时候大家只好开动脑筋想各种辙了。没注意危机的分布，也许又只说
明危机来得越来越频繁了。 anyway, it's an interesting video to watch.
(i don't count the time spent on this since this is part of study)
