CNN CNN Newsroom August 12, 2011
the dow closed down 600 on monday and up 400 on tuesday and down 500 points on wednesday and up 400 yesterday, and it was the first time in the dow's history we have seen closing numbers like this. drew? >> you could probably measure the heartbeat of traders the same way, up and down. tell us what happened in europe? they are trying to prevent the wild up and down swings. >> what they are doing is they are putting a temporary ban on short selling. what short selling is is when investors bet that a stock will go down in its price, and europe's version of our securities and exchange co...