Nasdaq investors had a great year in 2003, as the index soared 50% from start to finish. From its post-bubble low of 1,114, the composite index has nearly doubled, topping out recently at 2,153.83.

I say "topping out" because in the six weeks since hitting its high, the index is down about 5.5%. It's been in the red every one of those weeks. Generally, stock charts don't influence my decision making, but I do keep my eyes on the indices. The big picture seems to be telling us to get out of Nasdaq stocks, and a quick look at the exchange's biggest companies tells a similar story.

The top five companies, by weight, in the Nasdaq 100 are Microsoft (NASDAQ:MSFT), Intel (NASDAQ:INTC), Qualcomm (NASDAQ:QCOM), Cisco Systems (NASDAQ:CSCO), and Amgen (NASDAQ:AMGN). Let's look at their recent performance.

Microsoft is down around 8% from its high, while Qualcomm is down only 3%. Amgen and Intel have fallen 12% and 15%, respectively. And the big loser, Cisco, is off 22% from its high. However, with the exception of Microsoft, all these stocks are up tremendously from the beginning of 2003, leading me to believe valuation concerns are forcing these stocks down.

Using price to earnings (P/E) as a proxy for value, I compared the big five's current valuations to where they were as of Dec. 31, 2002. At close of business yesterday, Microsoft's P/E stood at 32.3, compared to a P/E at the end of Dec. 2002 of 30.87. Intel, the big gainer last year, currently has a P/E of 34, slightly higher than the P/E of 32 at the end of 2002. Thanks to tremendous earnings growth in 2003, Cisco's P/E is down from 50 to 37, and Qualcomm's P/E is down from 79 to 54. Finally, Amgen had no P/E in 2002 because of a net loss, and currently sports a P/E of 37.

So what does all this mean? Based on a sampling of the largest Nasdaq companies, the composite is likely valued similar to, or less than, it was in the early stages of the rally. One could argue -- and I would -- that these stocks are overvalued in an absolute sense. But that didn't keep them from rising then, so why should it now?

Motley Fool contributor Chris Mallon thinks everything costs too much, but he does own shares of Microsoft through his private investment partnership.