Do think about when you'll retire. Your "time horizon" is key. Someone in their 20s should be much more aggressive than someone in their 50s or 60s. "For those in their 20s and 30s and even some in their 40s, they will have decades until retirement and should take market swings in stride," said Rob Seltzer, a CPA at Seltzer Business Management in Los Angeles. "They are a small blip on the radar, so to speak, during their careers." If you're less than five years away from retirement or have already retired, you should be more conservative with your investments.

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Do check your asset allocation. Younger investors need to keep in mind that the money in their 401(k) plans won't have to be tapped for a long time. "The drops may present some opportunities," said certified financial planner Roger Ma, founder of Lifelaidout and author of "Work Your Money, Not Your Life." "For those whose asset allocation has moved far from their original targets, they may want to adjust future purchases toward a higher percentage of stocks." Older investors may want to consider moving some stock funds that have over-performed and buying more fixed income investments. "As people get older and get closer to retirement, they should gradually tweak their allocations to have a larger allocation to bonds," Seltzer said. However, if you're investing in a target-date fund in your 401(k), the allocation of stocks and bonds automatically becomes less aggressive and more conservative overall as you get closer to your retirement date.

Don't rush to make decisions. Contact your financial advisor and have a conversation about the markets and your financial goals. Zaneilia Harris president of Harris & Harris Wealth Management Group