The day started out ominously enough with Japan's Nikkei (Index: ^N225) dropping 2.29%, but things continued to deteriorate across global markets. In Europe, the FTSE 100 (INDEX: ^FTSE) opened only slightly lower, but its losses built steam as the day progressed. At the close of London trading, the FTSE was down 2.3%, a large enough drop to make it the index's worst day of the year. Following up Europe's struggles was the Dow Jones (INDEX: ^DJI), which was down about 1.05% shortly before 12:30 p.m. EDT.

What's wrong?
What's causing today's drop? The most obvious storyline is a weak Spanish bond auction. The country issued new 10-year bonds that saw their yield come in at 5.61%, a 20-basis-point spike well ahead of the 4.9% bond rate from a month ago. As a result of the bond auctions, the focus once again swung back to the precarious state of Europe's financial sector, with Barclays dropping 5.1% on the day.

Then we have the "lingering effects" of the Federal Reserve's release of meeting minutes yesterday revealing that additional stimulus efforts wouldn't be needed unless the economy hit another speed bump. Since the minutes came out yesterday during trading, that storyline as an excuse for today's drop seems suspect. 10-year bond yields (INDEX: ^TNX) are actually dropping today, which is the opposite reaction you'd expect if people were overly focused on the Fed signaling less stimulus ahead.

The bigger picture
Even with a day like today, it's important to note this isn't exactly a "blood on the streets" situation. While today gives news outlets an opportunity to dust off their pictures of frustrated-looking traders, the total market run remains very strong across the year. Even with today's drop, the Nasdaq (INDEX: ^IXIC) still sits up more than 17% on the year. The Dow is up around 7%.

Even in Europe, a continent still routinely the subject of doom-and-gloom headlines, the situation this year has been relatively strong. The FTSE is up 2.4% on the year after today's close.

The point? When the market's roaring like it has been this year, there are going to be days with decent drops. The important thing as an investor is to keep your cool. So far this year, markets like the Dow and S&P 500 have been remarkably stable with few days seeing moves above or below 1%. That's a situation you'd expect to change, especially when contrasting the wild moves seen in the markets the past few years.

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