American investors are accustomed to the admonition, “Stay the course throughout all market conditions.”

Unfortunately, that’s easier said than done. When markets become volatile, our brains go into full-on lizard mode. Many investors sell everything and rush into cash; others feel the need to shuffle around portfolios somehow, selling a little of this and buying a little of that.

But for investors who put their portfolios on autopilot, there is far less portfolio shuffling, according to a recent study by investment management giant T. Rowe Price.

In particular, T. Rowe Price focused on target-date funds, which provide automatic allocations, based on the account owner’s time horizon. Over time, as the account owner approaches retirement, the allocations automatically become more conservative. The investor makes no decisions about his or her account, leaving the allocations to a predetermined glide path.

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Each target-date fund is named according to the year in which an account owner expects to retire — an investor with money in a 2040 fund anticipates retirement sometime around that year.

A growing number of employers offer target-date funds as part of their 401(k) plans, and program sponsors generally find that employees appreciate the set-and-forget nature of these products. According to a study released in April by the Employee Benefit Research Institute, 48 percent of 401(k) plan participants were using target-date funds at the end of 2014. Younger investors are the most likely to use the products rather than choosing from other available options.

But not all target-date options are the same. Different fund families offer their own products. Some are more costly than others. Some use more expensive actively managed funds, rather than index funds. Some include a wider array of asset classes to achieve a broader diversification.

In addition, account owners should be cognizant of whether their particular target-date fund invests up to the retirement date, or through it. Those that invest up to the retirement date

Nelson says there are several different kinds of target-date funds, including those that aim to invest “through” or past the selected retirement date, and those that aim to invest “to retirement” and not past the selected date. Some of the “to retirement” funds take a more conservative stance, because their investment mandate ends sooner.

However, while the “through retirement” funds may be more aggressive in the earlier years, the mix becomes even more conservative after the account owner retires.

The two largest target-date managers, Vanguard and Fidelity, both offer plans that hold 50 percent in stocks at the time of retirement. Over time, both shift the assets into a more conservative allocation. Several years after the target date, both plans stop making portfolio shifts pegged to a participant’s age and put investors into retirement income funds. These generally have little stock exposure, and rely heavily on bonds, cash and some commodities as a hedge against inflation.

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While there may not be much an account owner can do about his or her particular plan, as offered by an employer, the behavioral component of a “one-stop shopping” approach to retirement investing may help account owners stay on track, rather than trading in response to market conditions.

Investment management firm T. Rowe Price studied investor behavior during periods of market volatility. Researchers wanted to know how 401(k) plan participants responded as market conditions changed, and became increasingly nerve-wracking. They evaluated behavior of Investors using T. Rowe Price target-date products, focusing on 21 observation periods from July 25, 2009 through Jan. 25 of this year.

Among T. Rowe Price’s findings:

— The vast majority of plan participants stayed on track during market downturns.

— The small percentage that did make portfolio changes during volatile markets did not flee to cash en masse.

— Plan participants with all their money in target-date investments were the least likely to make changes in response to market downturns.

According to T. Rowe Price’s research summary, “What we discovered in looking at retirement plan participant behavior during different periods of market volatility was that participants who had 100 percent of their assets in target-date investments behaved differently than those who had some or none of their money in those investment vehicles.”

In a nutshell, the built-in diversification of target-date funds helps investors remain disciplined. If one asset class is in a downturn, something else is likely to pick up the slack — at least to some degree.

If you prefer a set-and-forget option in your 401(k), a target-date fund offers an easy way to save. If you believe you need some help remaining disciplined through various market cycles, the target-date fund may be a good option.

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Even if your plan offers active management (which is more costly and can be riskier than index-based choices), the habit of regular saving is better than avoiding your 401(k) because you object to particular plan features. Staying on target through regular investing, and letting compounding work for you, is by far the superior choice.

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Target-Date Funds Help Investors Stay the Course originally appeared on usnews.com