Wait a minute: What's happening to the stock market rally? It's possible that it is peaking. It happens.

It may be peaking in part because global markets are worried, yet one more time, about Europe and the euro. The Cyprus crisis is making things a little hairy -- because of fears that a run on Cyprus' banks will set off runs on banks in Italy, Spain and elsewhere. So far that hasn't happened, but that hasn't stopped the fretting.

The rally could also be peaking because it's mid-March, and the market tends to slump in the spring. And it's peaking because it looks a bit overbought.
All that said, the Standard & Poor's Index ($INX) fell 13 points to 1,546 on Thursday. The index is down some 19 points from its 2013 high of 1,563.23, set on March 15. That close, in turn, was just roughly 2 points below its all-time closing high of 1,565.15, set on Oct. 9, 2007.

The Dow Jones industrials ($INDU) were down 90 points to 14,421. The Nasdaq Composite Index ($COMPX) dropped 32 points to 3,223. The major indexes' losses were their worst since Feb. 25.

It's the S&P 500 that's got our attention. That 2007 all-time closing high has emerged as a strong resistance point. Every time the index closes in on 1,565, sellers take profits.

Maybe it's because of Cyprus. Maybe it's because 85% of the stocks in the index are trading above their 200-day moving averages. Historically, every time that percentage moves above 80%, it sets the stage for a pullback. Not right away, but within a few weeks.

Lastly the relative strength indexes of the major indexes recently hit levels that cried out, "Pullback!" These measure momentum, and when they top 70, the odds of a sell-off increase. The S&P 500 and Dow topped 90 on March 15. They ended Thursday at 65 and 74, respectively.

The obvious question is, then, if the market is peaking, what does that mean? There is not a clear picture yet. Bears are convinced Europe and/or China will sink the global economy.

Bulls believe the S&P 500 will push to new highs in 2013. The question is when: now or later on. Meanwhile, U.S. economic trends have been gaining strength, especially real estate and automotive. The jobs picture looks to be improving; jobless claims are at levels not seen since early 2008.

And don't forget the the Federal Reserve. The central bank, as Chairman Ben Bernanke said Wednesday, is in no rush to start raising rates -- because it worries about Europe and recent softness in domestic manufacturing.

The market weakness on Thursday was concentrated in materials, financial and technology stocks.

Oracle (ORCL) was off $3.47 to $32.30, its worst one-day loss in a couple of years. It was the worst performer among S&P 500 stocks and stocks in the Nasdaq-100 Index ($NDX). Blame a big earnings miss, reported late Wednesday, which the company attributed to a weak performance by its sales team. The Nasdaq-100 was off 31 points to 2,775.

Add to that slides by networking companies Cisco Systems (CSCO) and Juniper Networks (JNPR) after a downgrade. Cisco was the weakest of the 30 Dow stocks, but its decline also affected Hewlett-Packard (HPQ) and IBM (IBM).

Airgas (ARG) was the second-worst S&P 500 performer after Oracle. Chemical companies Eastman Chemical (EMN) and FMC Corp. (FMC) were also among the 10 worst performers.

Yahoo (YHOO) and BMC Software (BMC) were the Nasdaq-100 leaders. Yahoo jumped after an upgrade.

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