He was a trustee to the Rockefeller Foundation, a special adviser to U.N.

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Also keep in mind that you'll need to increase the amount you set aside by 3% to 5% a year to keep inflation from eating away at the fund, says Ken Weingarten, a financial adviser in Lawrenceville, N.

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"The amount of trade as a share of national income, the financial flows as a share of just about anything, are much larger now than they were back in the 1970s, " says Sachs, who is also an economic adviser to U.N.

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