Worries about export earnings, given Argentina's high debt-to-export ratio, increase the interest-rate spread the country pays over United States interest rates, which have themselves risen this year.

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According to Reuters, the two-year U.S. interest rate swap spread--a gauge of financial system stress--was quoted at a record high 166.5 basis points in Asia, suggesting that concern about defaults among banking counterparties were worsening.

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The Cleveland Fed inflation estimates, based on financial market data including the interest rate spread between ordinary and inflation-protected Treasury bonds, show expected inflation of 1.4 percent per year over the next ten years.

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The greater the spread between the high-interest debt and the rate of return on investment, the greater the financial advantage for paying off the debt first.

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American Express earns a net interest income on the spread between the rate it earns from un-loaned amounts sitting in bank deposits and short-term investments in financial securities and the rates at which it extends credit to card members.

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Take, for example, one indicator of the market's appetite for risk, the spread between swaps of fixed- and floating-rate interest payments (see chart).

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Yet, even after the central banks' announcement, dealers cited by TradeTheNews.com said that some interest rate spreads were still high, with the TED spread (which is price difference between three-month futures contracts for U.S. Treasuries and three-month contracts for Eurodollars) still above 30 basis points.

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Despite the recent rate decreases, private jumbo mortgages still provide a bigger-than-usual spread between the interest banks receive and what they are paying on deposits.

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