The hedge fund robots are winning again.
That's a key lesson from 2014, when computer algorithm-led investing produced stellar returns, beating most gut-driven human managers and dramatically recovering most of their losses from 2011, 2012 and 2013.
So-called managed futures funds-which trade the futures contracts of stocks, bonds, currencies and commodities-gained an average of 15.2 percent last year, according to Societe Generale unit Newedge. That beat virtually every other hedge fund strategy, including stock pickers, beat-up bond vultures and macroeconomic prognosticators. The average hedge fund gained in the low-to-mid single digits for 2014, according to HedgeFund Intelligence.
The biggest gains came at funds that practiced a "trend following" strategy. Those managers-who use computer models to bet on price movements in either direction and often perform best when clear patterns emerge over several months-gained an average of 19 percent, according to Newedge.
Several of the largest funds in the industry, including those managed by $3.8 billion Cantab Capital Partners, $4.7 billion Aspect Capital and $13.4 billion Man AHL , gained more than 30 percent. Funds run by Two Sigma, Winton Capital, Campbell and others also gained double digits.
"We've seen significant moves in a number of markets, and trend followers have been able to take advantage of them," said James Skeggs, global head of the Newedge prime brokerage alternative investment advisory group.
Winning-and often contrarian-positions included the pattern of oil prices falling, the U.S. dollar appreciating versus most other currencies, and government bond interest rates declining.
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AHL's flagship fund hit all three. Its computers picked up signals of the moves early, and the fund gained about 33 percent through December, according to private performance information obtained by CNBC.com
AHL profited from bond price gains in Italy, France and Sweden, the opposite of what many discretionary traders predicted given already-low interest rates, according to a person familiar with the performance. AHL also shorted crude oil as it tumbled and went long the U.S. dollar as it appreciated versus almost every other currency in the world given the country's relative economic strength.
The strong performance last year was a reversal from the previous three, when the fund lost money each calendar year. AHL managed $13.4 billion as of Sept. 30 and is led by CEO Sandy Rattray. A spokesman for the firm declined to comment.
The best performing manager appears to be smaller ISAM, whose flagship ISAM Systematic rose 62.4 percent in 2014, according to a spokesman for the firm. Lord Stanley Fink, the former CEO of Man, launched the now-$750 million strategy in 2010. The firm declined to comment on performance drivers.
Another big winner was Aspect. The trend follower, led by CEO Anthony Todd, gained more than 32 percent during 2014 in its flagship $4.35 billion Aspect Diversified fund. The largest return driver was a bet against the future price of Brent crude starting in July, according to a spokesman. Oil prices fell steadily over the rest of the year. Another winner was a long position in government bonds as the fund caught the contrarian trend of interest rates declining (the value of bonds rises as yields fall).
Leda Braga's BlueTrend fund also caught the rising bond price pattern in developed markets, as well as gains for the U.S. dollar, according to a person familiar with the situation.
Braga's $7.8 billion BlueTrend gained 13.3 percent in 2014 through November, according to performance information obtained by CNBC.com. The fund was previously a unit of hedge fund giant BlueCrest Capital Management but spun out this month under Braga's new Systematica Investments. BlueCrest still has an undisclosed stake in the new firm, which has about 100 employees and more than $8 billion under management.
"Systematic trading started 2014 as the least-loved asset class and has ended it as the best performing in part as a result of having positions opposite to the consensus," said Ewan Kirk, Cantab's chief investment officer.
The success of managed futures comes after years of poor performance.
Strategy practitioners complained that returns were hurt by the continued intervention of central banks in the economy, which made the prices of many types of securities relatively stable. They were also challenged by the low rate of return on cash because of near-zero interest rates (funds tend to have lots of cash on their books relative to other strategies because the futures contracts they invest with don't require that the full amount of the bet be paid upfront).
Losses at most funds in 2011, 2012 and 2013 meant that managers made little money for themselves (hedge funds can't charge a performance fee on a loss) and investors redeemed more than $18 billion from managed futures funds over the first three quarters of 2014, reducing assets to $312 billion, according to BarclayHedge.
"People have been asking if CTAs are dead. This year has shown the answer to be a resounding 'no,'" said Newedge's Skeggs, referring to commodity trading advisors, another name for the strategy.
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Not every managed futures fund made money.
Jaffray Woodriff's Quantitative Investment Management (QIM) lost 8.74 percent through November in its main Quantitative Global Program. Other losing funds were those managed by Australia-based Kaiser Trading Group (down 0.13 percent) and Revolution Capital Management (down 14.5 percent).
Jim Curley, a marketer at $538 million Revolution, said its losing Mosaic Institutional fund attempts to have no correlation with mainstream managed futures funds by taking a relatively short-term investing approach. In other words, longer term trends made the most money this year, but the fund wasn't set up to take advantage of them.
"Many of our clients have said that if our performance were to drift to being highly correlated to long-term systematic, they probably would redeem their investment. They bought chicken soup and don't want us to become beef barley," Curley said, noting the fund gained 16 percent in 2013 as others faltered.
Kaiser CEO Tony Kaiser called 2014 results "disappointing" and blamed it on correcting markets in the first quarter of the year. He said tweaks to the fund's model improved performance over the rest of the year and added that combined with gains in 2013 (up 7.25 percent) the firm is in "a good position to move forward."
A spokesman for QIM declined to comment.
Managers predict more gains this year.
"With inter-market correlations having fallen and global macro-economic imbalances having become increasingly evident, we believe that market conditions for trend-following have generally improved-and that the prospects for 2015 are correspondingly good," said Aspect CEO Todd.
Adam Tremper, director of marketing at $4.5 billion Campbell & Co., agreed that more patterns like those that occurred in 2014 would be a boon.
"As a systematic manager, it's really not about one set of market conditions persisting over another," Tremper said. "It's more about having directional movement and the right degree of divergence across global markets."