This often results in deterioration of balance sheets as companies borrow more and leverage themselves up.
Two of the largest ever investment-grade bond deals came to the market in 2013, with Apple issuing $17bn (£10.3bn) in April and Verizon selling a colossal $49bn in September. Mr Murfin believes this trend could accelerate in 2014, which will have repercussions for credit spreads.
“Investment bond yields have done very well since 2009, so there’s not much of a cushion to compensate you if companies decide to embark on an aggressive re-leveraging exercise,” he cautions.
Alison Warner is a freelance journalist