Margin is the amount of profit a company makes on a sale.

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Competition suits customers, but it also carries the risk that clearing-houses will water down standards on the amount of margin they demand, for instance to win deals.

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Meanwhile, margin debt, or the amount of money that investors have borrowed to invest in stocks, is climbing.

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Traders typically put down just a small percentage of a gold contract's full value in order to trade it, and this amount, known as margin, must be increased when prices fall.

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ExxonMobil does not care if the margin increases because they have the full amount anyway.

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Independents will shift back and forth, but if they split 49% to 49% (with the rest going to minor candidates), then Mr. Obama's vote total would be shaved by 1.1 million and Mr. Romney's would grow by an equal amount, cutting the president's margin to 1.4 million.

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If it falls by a like amount, your investment will be wiped out and your account subject to a margin call.

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Until mid-May, bullion dealers could place gold import orders with a designated bank by paying a margin upfront and the rest on delivery, but a new rule stipulates they pay the entire amount before importing.

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