Some market watchers have called 2014 the year of the activist investor. A new study says 2015 will be even more active for the activists.

According to the report, 344 companies were targeted in 2014 by activists, mostly hedge funds, looking for some kind of shakeup. That was up from 291 from the same funds in 2013. The study was co-produced by research firm Activist Insight and law firm Schulte Roth & Zabel, which has worked for activist investors in the past.

As a group, activist funds now manage $237 billion, but the report doesn’t state if, or by how much, that figure has grown.

The report also suggests that shareholder activism will only grow and get louder in 2015. A slower economy around the world means that more large companies will have trouble growing. That opens the door for activist campaigns like we have seen with DuPont, giving investors more leverage to push for acquisitions or split-ups or some other form of corporate restructuring. How a company’s management is performing given the broader economic climate might not matter as much.

Activist Insight and Schulte’s report also says that activists have raised a lot of money, which means they are here to stay. But investments in hedge funds, unlike, say, private equity firms, tend to be pretty fluid. There are few lock-ups, so the size of the funds and the amount of money activists have to invest will depend on the success of these funds.

The report names Starboard Value, which is run by Jeff Smith, as the most successful activist investor of the year. Last year, after mocking Olive Garden for not salting its pasta water, Smith got the entire board of the chain’s owner, Darden Restaurants DRI , thrown out.

Carl Icahn slipped to No. 4 on the list of top activists for 2014, from No. 1 the year before. Given that Icahn Enterprises IEP stock is down nearly 5% in the past year, versus being up more than 100% the year before, perhaps the investor’s drop in the rankings should have been larger.

The question is whether activists really know how to run companies any better than the typical executives in corporate suites. Or are activists winning just because shareholders are itching for any change? According to the report, in 2014, nearly 75% of the time, activists were successful in getting companies to make at last some of their requested changes. At the same time, the average activist fund was up 4% last year, versus 13% for the market.

It might be too soon to tell if activism is good or bad for corporate America. But if the gap between activists’ success in getting companies to do what they want and their subsequent investing performance continues to widen, activists won’t be around long enough to find out.

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