Two drivers for the corporate debt market have been anticipation of higher interest rates and foreign demand. With the Federal Reserve expected to raise rates in the near future, borrowers are hurrying to lock in low borrowing costs. International demand for higher-yielding debt issuances as foreign yields have been materially lower and even negative has also driven more firms to issue debt in lieu of equity.
Companies increasing leverage while it's still cheap
Defaults in 2017 have been much lower than in recent years with only about $9.7 billion in bonds defaulting; in comparison, $29 billion and $31 billion in bonds defaulted in 2016 and 2015, respectively.