Exactly how the affluent divvy up their portfolio pie, however, is largely dependent on how they made their money and just how much they have in the bank.
The ultrarich, for example, often have highly concentrated holdings, said Simon Smiles, chief investment officer for UHNW clients at UBS Wealth Management.
"A lot of their wealth is often in a small number of assets or even in one asset," he said, noting two-thirds of the world's UHNW population is self-made. "There is an emotional side to it, so it's natural that they would want to continue to invest in the businesses that they founded and made their fortunes with."
The resulting lack of diversification, however, renders them vulnerable to competition, credit, technology and geopolitical risk. "The first rule of portfolio construction is diversification," said Smiles.
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Due primarily to their retirement status—roughly 71 percent are either retired or semiretired—those with a net worth of $5 million or more also keep a disproportionate percentage of their money under the mattress.
Roughly 11 percent of their assets are held in certificate of deposit accounts, with an average balance of more than $300,000, on which they receive minimal investment return, according to a 2013 survey by Vanguard and research firm Spectrem Group.