The key was the weak retail sales report that helped bond yields come in.

You never get drops of this magnitude without something serious going on. It's not a pretty picture, and it clearly caught a lot of people off guard.

Right now, they're close to capacity, so that relief valve isn't there.

We were overdue for some profit-taking after a great run.

Just when you think you're almost out of the woods, Wall Street has a way of changing the subject. The focus now is, how much will the economy slow and how much of a negative effect will that have on earnings.