The stock market has been posting gains the past few days.

After two very tough months to start 2009, what could go wrong?

Plenty, especially if you are focused on just the Dow Jones Industrial Average.

The Dow Jones has many financial-related companies, like Citibank, JP Morgan, Bank of America, American Express and quasi-financial stocks like General Electric and Caterpillar Tractor, which perform extensive lending and financing.

Remember, the financial stocks have led the charge the last two weeks, after Citibank’s CEO circulated a memo to employees announcing the bank did well in January and February.  But two months do not make a full quarter, and the banks have posted significant losses in the previous quarter, as mentioned before.

In fact, JP Morgan CEO James Dimon mentioned on Friday, March 27, 2009 that March is shaping up to be a difficult month.  And financial stocks promptly swooned, bringing the rest of the market along with them.

What else could go wrong?

On Tuesday, March 31, we will finally hear the final revised 4th Quarter GDP numbers.  Remember, one month after each quarter, we get preliminary GDP numbers.  Then one month later, we get revised GDP numbers.

Then, at the end of the following month — which is also the end of the NEXT quarter — we receive the final revised GDP number.

The market took a beating on each of the previous two GDP announcements at the end of January and also February 2009.  If the number on Tuesday is revised downward, watch out.

We also will receive preliminary 1st quarter GDP numbers (1st quarter 2009) one month from now, at the end of April, 2009.  Fasten your seat belts.