The psychology that has sent precious metals soaring could change suddenly if stocks heat up or economic data improve, said James Swanson, who helps oversee $237 billion at Boston-based MFS Investment Management.

"People may decide they don't look so pretty," he said in a telephone interview. "I like things that grow."

Gains in the franc may be limited after the Swiss National Bank on Sept. 6 set a ceiling of 1.20 versus the euro, the first such move since 1978, and pledged to defend the target with unlimited currency purchases. Concerns that Europe's debt crisis is worsening and the world economy is slowing pushed the franc to a level the bank described as massively overvalued.

"I wouldn't expect to make money with those assets unless something bad happens," Jack Ablin, chief investment officer at Chicago-based Harris Private Bank, said in a telephone interview. Ablin, who helps manage $55 billion, said stocks are cheap relative to earnings prospects, with the Standard & Poor's 500 Index down 5.5 percent this year.

Investor Deposits

Half of Permanent Portfolio's equity portion is in real estate and natural-resources companies and half is in aggressive-growth stocks, according to its website.

Diversification helped Permanent Portfolio in 2008 as it lost 8.4 percent, compared with a plunge of 37 percent for the S&P 500 Index and 28 percent for the typical balanced fund. The fund lost money in only three other years: 1984, 1990 and 1994, Cuggino said. It rose 6.7 percent this year through Sept. 13.

The performance has caught the eye of investors. Permanent Portfolio drew $3.9 billion in net deposits in 2010 and $3.6 billion in the first seven months of 2011, Morningstar data show. BlackRock Global Allocation Fund is the only better- selling rival in the balanced category this year, according to Morningstar, with $4.5 billion in deposits through July.

'Good Luck'

Cuggino regularly rebalances to keep the asset weightings in place, he said.

The security selection hasn't been particularly good, said Morningstar's Yang. Investors could do better by copying the fund's asset allocation using low-cost exchange-traded funds, she wrote in a March 29 research note. ETFs track indexes and trade throughout the day like stocks.