Although we don't believe in timing the market or panicking over market movements, we do like to keep an eye on big changes -- just in case they're material to our investing thesis.

What: A day after climbing 14%, shares of Citigroup (NYSE: C) fell as much as 11% along with the broader market.

So what: Banks are invariably tied to the health of the economy and with increasing concern about a double dip, or at the very least slower than expected growth, they are all falling fast. With the global presence Citigroup has built, a default in Europe and slowing investment-banking activity are weighing on investors' minds.

Now what: Over the past week, bank stocks have exaggerated the moves of the market as concerns about European debt, an overall economic decline, and of course fears borrowers will stop borrowing have hit the market. Citigroup is leading the financial sector lower with Bank of America (NYSE: BAC), Goldman Sachs (NYSE: GS), and Morgan Stanley (NYSE: MS) also taking big tumbles today. Right now I can't handle the roller-coaster ride the banking industry is on and will stick to stocks that have less exposure to the problems going on in Europe.

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