4 ms·

Tldr; we have no idea

• ekianjo 9y ago
  thats the right summary of this article.
• dboreham 9y ago
  I'm surprised that nobody has mentioned what seems to me to be the obvious precipitating factor: that some guy went on national TV on Jan 30 and boasted that he was responsible for a massive increase in the stock market. When I saw that I immediately felt a warm and fuzzy feeling for the fact I had decided not to buy any stocks (except AMD) over the previous few months. I think that many people who had only half been following the market heard that claim in the speech, causing them to pay renewed attention to market values, check on their portfolio, realize that there was clearly a bubble, then decide to sell.