Hedge fund snapshot: Just how big are they?

A new report on the hedge fund industry underscores just how big it is: $2.6 trillion in 11,000 funds.

The research by alternative investment tracking company eVestment aggregated information from 10 databases that collect voluntarily submitted data by hedge funds. After cleaning the data and removing duplicates, eVestment found that there are 7,524 traditional hedge funds, 1,723 managed futures or commodity trading advisors (CTAs invest using futures contracts, often for commodities) and 2,074 funds of hedge funds. Those funds were managed by more than 4,500 separate firms.

Together, those funds managed $2.66 trillion in 2013. Traditional hedge funds represented $2.3 trillion or 83.8 percent of the total with the largest funds, those over $1 billion in assets, controlling two-thirds of overall assets.

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Interestingly, fewer funds are reporting their performance to multiple databases despite looser rules on marketing and competition to snag new investor dollars.

The proportion of funds reporting to two or more databases decreased by 1.82 percentage points from 2012 to 2013. The proportion of funds reporting to at least one database also increased by just 1.82 points to 63.69 percent.

The percentage of funds reporting their assets under management and performance increased from 78.4 percent in 2012 to 81.2 percent in 2013.

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Critics have said there are too many hedge funds given their high client fees. The high number of hedge funds means it's more difficult to exploit market inefficiencies, since profitable but niche opportunities quickly become crowded trades.

The Absolute Return Composite Index, which aggregates hedge fund returns across all strategies, gained 3.79 percent this year through July. By comparison, the S&P 500's (^GSPC) total return was 5.66 percent and Barclays Aggregate Bond Index (NYSE Arca: LAG) gained 2.35 percent.