LONDON -- The Dow Jones Industrial Average (INDEX: ^DJI) is likely to open slightly lower today, as eurozone concerns come to the fore again following Spain's double credit-downgrade by rating agencies Moody's and Egan-Jones late yesterday. At home, a raft of key economic data is due that could also impact on the day's trading.

Data due today includes weekly jobless claims, expected to be down 1,000 at 376,000. Also out is the May Consumer Price Index -- expected to be down by 0.2% -- and the first-quarter current account balance, which is expected to be down by $134 billion, against $124 billion in Q4. EIA weekly gas storage figures are expected to show a further rise on last week's levels, which should keep natural-gas prices down.

In Europe, Spain's downgrade drove yields on its 10-year bonds to spike to a record 7% this morning -- a level that is considered unsustainable and has triggered previous eurozone bailout requests. This contributed to increased pressure on Italy, Europe's third-largest economy, which sold 4.5 billion euros of three-year bonds at a yield of 5.3% this morning, up from 3.9% last month. Commenting, Gary Jenkins, director of Swordfish Research, said, "We are fast approaching the point where both Spain and Italy may have to be removed from the market."

In London, the FTSE 100 (INDEX: ^FTSE) was down by 0.6% at 7 a.m. EDT following negative reaction to Spain's downgrade and general rising concerns about the eurozone's economic problems. Individual companies helping to drag the market down included satellite broadcaster British Sky Broadcasting (LSE: BSY.L), which was down by more than 6% following news of its latest and rather costly $3.6 billion deal to show 116 live football matches over the next three years in the U.K.

At 7 a.m. EDT in Germany, the DAX was down by 0.4%. In France, the CAC 40 fell by 0.2%, while Spain's IBEX 35 was up by 0.4%. In Greece, the index of 20 leading companies rocketed by 10% after Greek banking stocks rose 20% on rumors that unpublished opinion polls suggest pro-bailout parties are most likely to win this weekend's elections. Greek banks have previously been pushing the market down, following a slow-motion bank run this week that has seen daily withdrawals of between 600 million and 900 million euros, up from normal levels of 100 million to 500 million euros.

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Companies due to report earnings this morning include Kroger, Smithfield Foods and Pier 1.

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