Russ Robertson, a certified financial planner with WealthCrest Financial Services, offers a scenario where 50 percent of that stock allocation is invested in large-cap stock funds, 30 percent in small-cap stock funds and 20 percent in international stock funds.
Robertson and other advisors break it down further. For instance, Ramnani's allocation recommendation for clients has recently changed.
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"The research we've done for our clients shows that international [markets], specifically emerging markets, are going to produce more growth compared to U.S. domestic equities in five, 10 or 15 years," Ramnani said.
"So for someone who is younger, it makes sense to have more exposure to emerging markets," she explained, adding, "We used to put more than 10 percent of a client's portfolio [in emerging markets], but now we're definitely doing more than that."
Ramnani cautions, however, that without professional guidance, it can be tricky to figure out exactly how far above 10 percent that allocation should be.