Bonds are supposed to be boring. Stocks are supposed to beexciting. This year, the opposite is true.

While U.S. stocks have held remarkably steady in 2015,longer-dated Treasuries have been jumping all over the place,posting some of the biggest back-to-back gains and losses on recordas the Federal Reserve talks about raising interestrates and European leaders duke it out over a bailout forGreece.

The trend is wearing thin on some of those bond investors whosought out a traditionally safe place to park their money. Theyyanked US$327 million from exchange-traded funds focused on thislonger-dated debt in the past week alone, and $1.4 billionyear-to-date, Bloomberg data show.

“It really is a function of bonds being the center of the stormin terms of investors ultimately being concerned with risingrates,” said Marvin Loh, senior fixed-income strategist at BNYMellon Global Markets. “We pushed rates so low at the beginning ofthe year and we possibly overshot.”

In January, investors piled into longer-term Treasuries as theyworried about the possibility of deflation and imagined a globaleconomy that failed to regain real momentum anytime soon. The debtmaturing in more than 15 years posted a record gain of 8.9 percentfor the month, with yields on the notes falling to 2.2 percentcompared with a 10-year average of 3.9 percent, Bank of AmericaMerrill Lynch index data show.

Yields on the notes have since risen to 3.1 percent and the debthas generated a 13.6 percent loss. That's equal to an estimated$208 billion that's been wiped out in the $1.2 trillion pool ofdebt.

What changed? The European Central Bank embarked on a 1.1 trillioneuro bond-purchasing program to ignite growth, and the effortsseem to be working. Meanwhile, the U.S. economy is emerging from afirst-quarter slump and oil values have rebounded, leading to moreconcerns about inflation than declining consumer prices.

Take all that turmoil and heartache for investors who weren'tpositioned for it, and contrast that with the incredibly boringcalm that's washed over U.S. stocks. The Standard & Poor's 500index hasn't posted a gain or loss of 2 percent or more for 126days, the longest streak since one ending in February 2007,according to data compiled by Bloomberg and Deutsche Bank AG.

As the Fed moves closer to its first rate hike since 2006, it'shard to see how bonds will become much less volatile anytime soon.The question is whether stock investors will take notice and jointhe ride.

Copyright 2018 Bloomberg. All rightsreserved. This material may not be published, broadcast, rewritten,or redistributed.