It’s the quintessential question in the investing world: Is it better to go with a cheaper index fund that simply tracks the market? Or should you turn to a more expensive, actively-managed fund where a portfolio manager — a good one at least — might be able to bring in a bigger return?

New data may offer some guidance.

A metric introduced by investment-research firm Morningstar at its annual investment conference compares the returns by actively-managed funds to those of index funds in the same category, taking into account fees and which funds were shut down.

The results weren’t pretty. Actively managed funds lost out to their passive peers in nearly every asset class during the 10 years between 2004 and 2014, according to the report. Active funds were also more likely to get merged with other funds or closed.

Over the long term, active management paid off most for small-cap, mid-cap foreign stocks and intermediate-term bond funds, which performed better than index funds and were more likely to stay open. There was only one category where more than half of active funds performed better than the average index fund over the 10 years: U.S. mid-cap value stocks, which did better than index funds 54 percent of the time.

In the short term, actively- managed bond funds showed more value. About 73 percent of actively-managed intermediate-term bond funds beat the average index fund over the three years ending in 2014. About 70 percent of active bond funds beat the average index fund over the three years ending then.

No stock fund category saw more than 50 percent of active funds beat out index funds over those short time periods.

Another trend worth noting: Active funds with lower fees were less likely to be shut down that funds with higher fees, but in nine out of the 12 categories studied, they still had lower returns than the average passive fund.

Of course, funds won’t necessarily perform in the future the same way they did in the past. The research isn’t meant to settle the active versus passive debate but to give investors a sense of their chances for finding a winning fund manager in different asset classes and categories, the report notes.

Some financial advisers say investors should use both kinds of investments, by using low-cost index funds to make up the bulk of a portfolio and reserving active funds for investing in more complicated or niche markets where the wits and instincts of a smart human being might provide an advantage and boost returns.

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