The volume of junk-bond inflows is falling from a peak of $5.5 billion in February, with investors funneling less than half of that into funds the following month, EPFR data show. Speculative-grade bonds have gained 0.08 percent this month after advancing 5.1 percent this year through March 31, according to Bank of America Merrill Lynch index data.

“In the last week or so I've sensed a higher degree of nervousness in the market,” said Bonnie Baha, head of the global developed credit group at DoubleLine Capital LP in Los Angeles, where she helps oversee $32 billion.

While global debt issuance has soared since the 2008 financial crisis as companies reacted to the withdrawal of bank credit by rushing to issue bonds, proportional trading volumes have dwindled. Bond sales peaked at $3.9 trillion globally in 2009, an increase of $1.1 trillion from the previous year, and have held at about $3.2 trillion annually since then, data compiled by Bloomberg show.

Securities equivalent to about 96 percent of the outstanding market are traded in the U.S. every 12 months, down from about 180 percent at the peak in 2005, Citigroup data show.

Default Swaps Rise

Elsewhere in credit markets, a benchmark gauge of U.S. company credit risk increased for a second day, with the Markit CDX North America Investment Grade Index, which investors use to hedge against losses or to speculate on creditworthiness, climbing 1.2 basis points to a mid-price of 100.6 basis points as of 12:18 p.m. in New York, according to prices compiled by Bloomberg.

The index typically rises as investor confidence deteriorates and falls as it improves. Credit-default 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 U.S. two-year interest-rate swap spread, a measure of bond market stress, rose 0.69 basis point to 29.88 basis points as of 12:19 p.m. in New York. The gauge widens when investors seek the perceived safety of government securities and narrows when they favor assets such as corporate bonds.

Bonds of Chesapeake Energy Corp. are the most actively traded U.S. corporate securities by dealers today, with 153 trades of $1 million or more as of 12:19 p.m. in New York, according to Trace, the bond-price reporting system of the Financial Industry Regulatory Authority.

Bond trading has become more difficult because investment banks won't commit so much capital to hold the securities on their books as regulations on risk-taking loom and financial companies remain concerned that Europe's sovereign-debt crisis may escalate.

Dealers that are authorized to buy Treasuries directly from the government have reduced corporate debt holdings to $45.6 billion from the $235 billion they held at the peak in October 2007, according to Fed data compiled by Bloomberg.

“The quickest way to create liquidity when you have these outflows is to sell what you can,” not necessarily what you want to, Baha said. “If everyone heads for the exits at the same time, given the poor liquidity that we're already seeing in the market, you're going to see some incredibly volatile pricing moves.”

Holdings dropped to $40.4 billion on Feb. 22, the lowest since June 2002, according to the data.

Liquidity Drops

“Each and every investment bank has significantly reduced the capital it's prepared to commit to taking risk in recent years,” said Constantinos Antoniades, the founder of Vega-Chi Ltd. in London, which operates an electronic trading system for high-yield and convertible bonds.

Credit markets can freeze and prices plunge, as happened in 2008. From the end of August to Dec. 15, the Barclays Capital High Yield Market Value index plunged 44 percent, before starting to rally at the end of that year.

“Liquidity, even for the biggest clients, has dropped dramatically,” said Peter Tchir, founder of TF Market Advisors in New York.

The trend of volume ebbing is global. In euro- and pound-denominated debt, 12-monthly turnover has slipped to about 40 percent of the market from as much as 120 percent in 2004, according to New York-based Citigroup.

As trading volumes decline, there are few signs that buyside firms and brokerages can swiftly replace the volume that large Wall Street banks have withdrawn from the market.

“One way to ensure there is liquidity in the market and there is no risk of a shut-down at times of market stress, is to reduce reliance on investment bank dealer desks,” Antoniades said.

Agency brokers, dealers that seek to match buyers and sellers of securities without holding them on their own books, as well as independent electronic platforms that allow clients to enter buy and sell orders without going through an intermediary are trying to gain ground.

Over time, electronic trading systems, combined with clearinghouses for credit derivatives and new instruments such as exchange-traded funds that track bond indexes, will help replace the market makers, according to Tchir.

Bypass Banks

BlackRock Inc., the world's largest money manager, said April 12 it plans to start a bond-trading system that will help investors to bypass investment banks. The firm, which hopes to attract institutional investors including sovereign wealth funds and insurers to the platform.

For now, fund managers are taking preemptive measures to address shrinking secondary market volumes.

Because it is hard to trade, managers hold on to cash to meet redemptions to avoid having to sell into a rout, said Ashish Shah, who helps oversee about $420 billion as head of global credit investments at AllianceBernstein LP in New York.

The possibility that the market might seize is “a legitimate concern but portfolio managers have that concern and manage with that in mind,” he said in a telephone interview.

Bloomberg News

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