Was one of your New Year’s resolutions to manage your finances better in 2016? Perhaps your list included saving more, spending less, paying off credit cards and student loan debt. Here’s another important task to add to your financial health to-do list: rebalance your portfolio.

Don’t worry — it’s not that hard. But for do-it-yourself investors, it’s important to analyze your current asset allocations at least once a year to make sure recent market fluctuations haven’t stretched your stock or bond allocations in the wrong direction.

Your portfolio can get unbalanced. Let’s say you have a baseline portfolio allocation of 70 percent stocks and 30 percent bonds. If the equity markets posted strong gains since you last looked at your portfolio, you may now be sitting at an allocation of 75 percent stocks and 25 percent bonds.

“This larger allocation brings with it more market exposure and may be riskier than that investor can tolerate. Rebalancing will bring the portfolio back into alignment so the investor can sleep at night,” says Ann Minnium, certified financial planner and principal at Concierge Financial Planning in Scotch Plains, New Jersey.

You will need to rebalance back to your baseline allocation target — it’s as simple as selling 5 percent of your stock allocation and buying 5 percent of your bond investments to bring you back to your 70/30 goal. “The whole idea of rebalancing is selling the winners and buying the losers and not letting your portfolio get off track from your goals and objectives. You want to realign the portfolio for your pre-established risk-level,” says Todd Douds, director of operations at Fort Pitt Capital Group in Pittsburgh.

Rebalancing can bring psychological challenges, and the disciplined investor needs to stay focused on long-term financial goals. “Our experience is that investors who are left to their own devices struggle with the actual implementation of rebalancing: selling what’s high and buying what’s low,” says Zack Shepard, vice president of communications at Matson Money in Scottsdale, Arizona.

“It’s very similar to a diet. Almost everyone knows how to lose weight — eat less and move more — but when the cheesecake comes around after dinner, it’s really hard to force yourself to refuse even though you know you should. In investing, it’s really hard to force yourself to sell what is up and buy what is down, but that is what you have to do,” Shepard says.

Review your allocations. This is also a good time to review your allocation to make sure it’s still appropriate for your goals and determine if any circumstances have changed that will alter your investment plan, Douds says.

If you aren’t sure how much you should allocate to stocks and bonds, there’s isn’t a surefire formula — but there are some guidelines. A rule of thumb you can use as a starting point: Subtract your age from 100, and that’s the percentage that your portfolio should be in stocks; the rest should be in bonds. However, age is only one consideration to determine a particular asset allocation. “There is no one-size-fits-all allocation at any age,” Minnium says.

How risk-averse are you? Financial advisors say it is important to stretch out the risk continuum and invest in stocks to grow your money for retirement. However, a 2014 UBS survey found that many investors continue to avoid the stock market and that millennials are even more skittish about equities. The survey revealed that a typical millennial holds 52 percent of their portfolio in cash and 28 percent in stocks.

Investors should take into account their age, goals, risk tolerance and other income sources and assets, says Derek C. Hamilton, certified financial planner at Indianapolis-based Elser Financial Planning. “It varies greatly from person to person. In your 20s, a 90 percent stock and 10 percent bond allocation may be appropriate. In your 60s, you might start the discussion at a 60 percent stock and 40 percent bond allocation, but you may not end up there for good reason,” he says.

Investors can also look to target-date mutual funds for additional guidelines. For example, a 30-year-old has about 35 years to retirement. The Vanguard Target Retirement 2050 Fund (ticker: VFIFX) holds 89.8 percent in stocks and 10.1 percent in bonds.

Do-it-yourself investors may want to consider using target-date funds in certain situations or for a portion of their portfolio. Many 401(k)s have target-date funds as the default investment option if the employee doesn’t specify an investment choice. “This is a much better default than cash,” Minnium says. “I also like target-date funds for investors with a small amount of money to invest. My son started his Roth IRA with $1,000, and he invested in a target-date fund, which enabled him to be completely diversified and well-allocated with only a small sum,” Minnium says.

However, for investors with larger sums of money, a target-date fund may not be the best idea, Minnium says. “They can cost more, and it may be difficult to fine-tune their asset allocation without accessing other investments.”

How often is enough? Mark your calendar for a once-a-year checkup on your portfolio to make sure it’s not out of whack with your goals and risk tolerance levels. “Rebalancing too often can be expensive due to transaction costs, which can weigh heavily upon returns. It’s also smart to rebalance if you have been lucky enough to inherit money or if you experience a significant change that affects your financial position,” Minnium says.

The important thing about rebalancing is that you do it systematically, not based on a prediction or feeling about the future, Shepard says. “We look at market dips as opportunities and rebalance if portfolios move away from their target allocation percentage. For example, if fixed income is up and equities are down, which is what is currently happening in markets, we will sell fixed income and buy equities.”

And don’t try to time the market. “It has been shown time and again that trying to outsmart the collective wisdom of the millions of smart, well-informed people who trade in the market is very hard to do consistently no matter who you are. Disciplined rebalancing keeps you away from that market-timing trap,” Hamilton says.

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Time to Rebalance Your Portfolio originally appeared on usnews.com