3. Rebalance to keep risk in check.
Wherever you set the asset allocation for your 401(k) account, it's going to shift as the market moves. (Many people use the formula of 120 minus their age to determine the percentage of equities versus fixed income.)
Maybe you're 40 years old and started with a 60-40 allocation of stocks versus bonds and cash, but there's been a runup in stocks, and now you're at 70-30. (Over the long term, stocks generally outperform bonds, so this is likely to happen eventually).
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What to do now: Is that bad? Not necessarily, because market movements are normal. But the changes may mean you are taking more or less risk than you intended. Rebalancing, by selling the outperforming funds and buying the underperforming ones, will keep risk in check by bringing you back to your ideal asset allocation.
These changes are tax-free in a 401(k). Also remember, Benke cautions that some companies have two settings: one for how new money is invested, and one for current funds. "Make sure these are both set to your desired asset allocation," he said.