"With fewer covenants to violate, 'covenant-lite' issuers were in a better position to weather the storm of the recession, which explains their outperformance in terms of defaults," it said.
But not everyone is convinced.
"New deals are different"
"Over the last six years, there haven't been many defaults, so you don't have a lot of good data to go on right now," said Steve Goldman, managing director at fixed income manager Kapstream Capital.
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"The new deals don't look like the old deals," he said. "When things go bad, companies aren't forced into austerity measures and that historically has led to more defaults."
Default rates are currently in the low single digits, but that could change, he said, noting that many borrowers, especially in Asia, have floating-rate loans and could see their cost of capital rise sharply if interest rates rise. Currently, the U.S. speculative-grade default rate is around 1.5 percent, according to data from S&P, which expects it to rise to 2.7 percent by June 2015.
During the Global Financial Crisis, markets priced in default rates of as high as 20 percent, he noted, adding that Kapstream hasn't really invested in the high-yield segment and is unlikely to change tack in the current environment.
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If relying on historical default rates rings a bell, it might be from the Global Financial Crisis, when the creators of mortgage securities relied on historical data showing mortgage default rates were typically low -- something that changed once lending standards deteriorated.