Better news came from the U.K., which is not part of the single currency zone. Corporate credit ratings in the country increased significantly across several bellwether sectors including manufacturing, construction, retail and professional services.
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"The European economy remains a concern to investors worldwide," said Matthew Debbage, president of Creditsafe's U.S. operations, in the report.
"Despite the U.K.'s thriving economy, which is validated by a significant jump in company credit ratings in four key industries, much of the rest of Europe is flat or in decline. Company credit ratings in Germany, France and Italy were down or flat in almost every sector."
The euro zone's fledgling recovery—which started at the end of 2013—has faltered in recent months, with gross domestic product (GDP) rising only 0.2 percent quarter-on-quarter between July and September. Policymakers are also battling with very low inflation and high unemployment.
In addition, Markit's flash purchasing managers' index (PMI) last week suggested that private sector growth declined in the euro zone in November.
The U.K. economy, by comparison, grew by 0.7 percent in the third quarter on the previous three months. Unemployment is declining, coming in at 6 percent in the third quarter, down from 7.6 percent a year earlier.
Credit ratings in Germany and France dropped slightly in the last 12 months, while those in Italy fell by a "drastic" eight points, according to Creditsafe.
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On Tuesday, the Organisation for Economic Co-operation and Development (OECD) warned that stagnation in the euro zone posted a serious danger for global growth.
"The euro area is grinding to a standstill and poses a major risk to world growth, as unemployment remains high and inflation persistently far from target," the OECD said in a report.