By John Glover May 14 (Bloomberg) — Insurers are leading the first monthly decline for corporate bonds since December on speculation they face losses on sovereign debt just as cleanup costs for the Gulf of Mexico oil spill loom. American International Group Inc. and Axa SA are among insurers whose bonds lost 1.09 percent including reinvested interest, according to Bank of America Merrill Lynch index data. That compares with the negative 0.83 percent return on debt issued by energy companies hit by BP Plc ’s oil rig explosion and the 0.68 percent loss on notes from banks, also big holders of debt of troubled European nations. Europe’s largest insurers hold more than 95 billion euros ($120 billion) of bonds issued by countries in the region whose struggle to fund record budget deficits prompted a $1 trillion international rescue, CreditSights Inc. data show. The Gulf oil leak from the explosion of the Deepwater Horizon rig may cost $12.5 billion to clean up, according to Sanford C. Bernstein & Co. analysts. “The insurers’ declines are primarily down to sovereign debt concerns because they’re investors in government bonds, agencies and so on,” said Luis Maglanoc , head of credit research at UniCredit SpA in Munich. “The costs of the Gulf accident are likely to be indirect, as people claim for injury or loss of livelihood for example, and will be in the future.” The extra yield over Treasuries that investors demand to hold bonds of AIG , the insurer rescued by the U.S. government, increased an average 105 basis points to 355 basis points since April 19, according to Bank of America Merrill Lynch index data. That’s the day before the Deepwater Horizon blew up. The spread on the notes widened 88 basis points this month. Credit Risk Falls Elsewhere in credit markets, the extra yield investors demand to own corporate bonds instead of government debt fell 1 basis point yesterday to 168 basis points, after soaring 28 basis points last week, the Bank of America Merrill Lynch Global Broad Market Corporate Index shows. The spread peaked at 511 on March 30, 2009, and dropped to as low as 142 on April 21. An indicator of U.S. corporate credit risk is on track for the biggest weekly drop since May 2009 after European leaders agreed to the almost $1 trillion aid package to prevent a sovereign-debt collapse. Credit-default swaps on the Markit CDX North America Investment Grade Index, which investors use to hedge against losses on corporate debt or to speculate on creditworthiness, rose 3.4 basis points to a mid-price of 101 basis points as of 5:23 p.m. in New York, according to Markit Group Ltd. The index dropped from 119 basis points on May 7. The retreat shows that investor sentiment has calmed following the Europe-driven rout last week that broadly pushed credit swaps to the highest in at least 10 months. Bond Issuance Rises Credit swaps pay the buyer face value if a borrower fails to meet its obligations, less the value of the defaulted debt. A basis point equals $1,000 annually on a contract protecting $10 million of debt. The contracts typically rise as investor confidence deteriorates and falls as it improves. Global corporate bond issuance this week rose to at least $14.1 billion, compared with $10.3 billion last week, according to data compiled by Bloomberg. CVS Caremark Corp., PNC Financial Services Group Inc. and FPL Group Inc. , owner of Florida’s largest utility, led debt sales in the U.S. yesterday. CVS , the largest U.S. distributor of prescription drugs, sold $1 billion of securities in maturities of 5 and 10 years, Bloomberg data show. The $550 million of 5-year notes yield 100 basis points, or 1 percentage point more than similar maturity Treasuries. The 10-year bonds yield a 125 basis point spread. Leveraged Loans Prices on the Standard & Poor’s/LSTA U.S. Leveraged Loan 100 Index , which tracks the 100 largest dollar-denominated first-lien leveraged loans, rose 0.26 cent on the dollar this week to 91.15 cents. The index has risen 54 percent from 59.2 cents on Dec. 17, 2008 and is down from its April 26 high of 92.9 cents. More than $110 billion in U.S. leveraged loans have been arranged this year, according to Bloomberg data, up from $33.9 billion during the comparable period in 2009. Over $370 billion of U.S. leveraged loans were arranged during the period in 2007. Renal Advantage Inc., a provider of outpatient dialysis services, is seeking $305 million of bank debt to pay a dividend and refinance debt, according to a person familiar with the transaction. Deutsche Bank AG, Barclays Plc, Bank of America Corp. and General Electric Co.’s financing unit are arranging a six-year $245 million term loan and a $60 million revolving credit line for the Brentwood, Tennessee-based company, said the person, who declined to be identified because the terms are private. Emerging-Market Bonds The extra yield investors demand to own emerging-market bonds instead of Treasuries is heading for its biggest weekly drop in nine months. Spreads fell 49 basis points since May 7 to 276, according to JPMorgan Chase & Co.’s Emerging Market Bond index. Gol Linhas Aereas Inteligentes is beating its biggest rival, Tam SA, in the bond market as Brazil’s economic growth accelerates amid a four-month rally in the real. Gol’s 7.5 percent bonds due in 2017 yield 7.72 percent, or 81 basis points less than Tam’s similar-maturity notes, after yielding 476 basis points more a year ago, according Bloomberg data. The relationship between the nation’s two largest airlines reversed because Gol gets 89 percent of its paid passenger miles from domestic business while Tam receives 41 percent of its miles from international business, according to April figures. The real’s 6.8 percent gain since Feb. 1 has reduced fuel and debt-servicing costs for Gol while hampering Tam’s revenue growth. Libor Increase The rate banks pay for three-month loans in dollars rose to the highest in nine months as concern over the quality of collateral needed to secure loans heightened financial institutions’ reluctance to lend. The London interbank offered rate, or Libor , for such loans climbed to 0.436 percent yesterday from 0.43 percent May 12, the most since Aug. 13, according to data from the British Bankers’ Association. Libor rises when banks become more hesitant to lend to potentially risky counterparties. The dollar Libor-OIS spread, a gauge of banks’ reluctance to lend, widened for a fifth consecutive day, reaching the most since Aug. 20. Libor has risen 16 of the past 17 days as the euro-area’s debt crisis stoked concern that regional banks’ holdings of bonds from countries struggling to cut their budget deficits, such as Greece, Portugal and Spain, will deteriorate in quality. The rate stabilized this week after the European Union announced the rescue plan. ‘Upward Drift’ “There is a natural upward drift in rates on a long-term basis,” said Marc Ostwald , a fixed-income strategist at Monument Securities Ltd in London. “There’s an underlying realization that counterparty risk is still there.” AIG said May 7 it paid about $20 million tied to property claims related to the oil spillage. The New York-based insurer said that while it couldn’t estimate casualty losses tied to the event until the cause is determined, the liabilities could have a “material adverse effect” on its results. The spill may cost insurers as much as $1.5 billion in claims, according to Transatlantic Holdings Inc. , the reinsurer sold by AIG. PartnerRe Ltd., the reinsurer that purchased Paris Re Holdings Ltd., faces claims of $60 million to $70 million, it said in an April 29 statement. Rig Explosion “Notably, Deepwater Horizon explosion losses could be an issue” for property and casualty insurers in the second quarter, Jay Gelb , an analyst at Barclays in New York, said in a note on April 30. Gelb called first-quarter earnings “mixed so far,” with premium income declining and price erosion in commercial insurance as underwriters go after new business “aggressively.” Average spreads on bonds of Axa have widened 36 basis points to 259 basis points, according to Bank of America index data. The Paris-based company has 9.6 billion euros of southern European government bonds, including 4 billion euros of Italian debt, according to New York-based CreditSights. Spreads on bonds of Aviva Plc, the U.K.’s second-biggest insurer, have widened 33 basis points to 387 basis points on average this month. Aviva is the U.K. insurer with the largest amount of government bonds, according to Bernstein Research. Insurance companies’ holdings of government bonds are closely linked to where they are based and European companies typically hold a bigger proportion of bonds than equities, said David Prowse, an analyst at Fitch Ratings in London. Of the bond holdings, about half is in government securities, he said. Assicurazioni Generali SpA , Europe’s third-biggest insurer, has 46.5 billion euros of Italian government bonds out of its 48.75 billion euros of southern European government debt, according to CreditSights. Spreads on Trieste, Italy-based Generali’s bonds have widened 46 basis points this month on average. European insurers hold 6 billion euros of bonds sold by Greece, whose debt crisis sparked a plunge in the securities of the region’s so-called peripheral nations, according to CreditSights. To contact the reporter on this story: John Glover in London at johnglover@bloomberg.net