Futures-trading funds missed their chance for redemption in October, once again falling victim to a spike in capital markets volatility that created casualties across the board.

So-called commodity trading advisers now face somewhat of an existential crisis as investors question their ability to provide downside protection during market reversals.

“[CTAs] had a bad February [and] a bad October, so that’s two months you wanted it to do well when the rest of the market was doing poorly,” said Philip DiDio, a portfolio manager at SECOR Asset Management, at the Gaining the Edge conference this month.

Hedge funds following months-long market trends fared the worst, losing money on reversals in energy and equity markets. The Societe Generale Trend Indicator, which mimics popular trend-following positions, fell 7.88% in October to go down 16.80% for the year. If the result holds, it would be the measure’s worst year since 2013.

Medium-term trend followers make up a large portion of the CTA sector, which also includes short-term programs and funds that trade against market momentum.

Graham Capital Management’s $6.8 billion Tactical Trend strategy lost 3.61% in October, leaving it down 5.48% for the year, according to Absolute Return data. The London-based Winton Fund also went into the red after dropping 2.55% in October, according to EuroHedge data.

FORT LP’s $2.8 billion Contrarian strategy, which attempts to anticipate market trends, fell 3.21% in October, according to Absolute Return data. The losses left the fund 3.49% in the red for the year.

Trend followers lost money during stock market sell-offs in February and October this year, calling into question the viability of their models. Last month, the funds were also wrong-footed by positions in global government bonds.

“In October, even more than February, there was also a knock-on effect of other markets that suddenly turned around,” said Jon Stein, chief executive of Kettera Strategies, a marketplace for futures-trading funds.

Performance troubles have investors questioning whether CTAs have a role to play in their portfolio. Patrick Roy, senior portfolio manager at the Canadian Medical Protective Association, said he has been reducing exposure to CTAs.

“For us, I don’t think they will play an important role, in the portfolio going forward,” Roy said at the Gaining the Edge conference. “…I’m not fully convinced about the negative correlation.”

Other critics say investors piled into medium-term trend followers under a misguided perception they protect capital in down markets. Several funds made money during the financial crisis by following trends in fixed income markets as equities slumped. But years of post-crisis easy money policies have thrown those relationships into doubt, forcing CTAs to adapt their own models.

Several systematic managers have looked to incorporate new, shorter-term signals into their algorithms. Others are experimenting with different kinds of trading strategies, such as mean reversion and similar trades typical of quantitative macroeconomic funds.

That includes Campbell & Company, the more than 40-year old systematic multi-strategy manager. Campbell’s Managed Futures strategy is experiencing its worst year on record, posting losses of 12.61% through November 7, according to HSBC data.

But Campbell’s Absolute Return strategy gained 1.2% in October, putting it up 6.7% for the year, a person familiar with the matter said. Gains in short-term and macro trading offset losses in strategies that follow market momentum, the person said.

Campbell is reoffering the Absolute Return strategy to investors with a founders’ fee structure, the person familiar said, citing high demand from institutional investors for systematic macro hedge funds.

Stein says several funds employing artificial intelligence weathered the sell-offs in February and October. Investors should encourage CTA managers to reconsider their models in light of performance struggles, he said.

“It’s up to their allocators to shake them free of their hubris,” Stein said. “I just don’t know if they always know the right questions to ask.”

October losses call into question trend follower promises on Absolute Return.