The main difference between aggressive and conservative portfolios comes down to the balance between stocks and bonds. There's little difference between the stock portfolio of a 20-something and that of a retiree, other than the amount of stocks each owns.
Within equities, financial professionals urge investors to make sure to diversify among domestic and international stocks, since they often move in opposite directions. Also include small- and large-cap stocks to capture the performance of different company sizes.
But investors don't need to slice their equities too thinly with alternative investments. "Alternatives are very confusing, and even a lot of advisors aren't that familiar with them," said Dory Rodriguez, wealth advisor with HighPoint Planning Partners.
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Real estate is an exception, and many financial advisors recommend 5 percent to 10 percent allocation toward real estate investment trusts in most portfolios. However, REIT dividends are taxed as ordinary income, so hold them in tax-sheltered accounts, such as 401(k) plans and individual retirement accounts, to avoid the tax hit.
When it comes to bonds, a mix of corporate, Treasury and high-yield bonds diversifies across industries and interest-rate exposure.