Ron Quigley, head of fixed-income syndicate at Mischler Financial Group, predicts a big month ahead for January, with up to $160 billion of sales, which would be a record. Others surveyed by Bloomberg are expecting about $112 billion of such debt sales this month, below last year's $134.9 billion in issuance for January, according to data compiled by Bloomberg.

2) Companies are still planning mergers and acquisitions, and they're borrowing money to do so. Even though there are fewer megamergers on the horizon, private equity firms have some big plans. These investors appear determined to put cash to work regardless of the relatively high valuations, according to my fellow Gadfly columnists Brooke Sutherland and Gillian Tan. And some of these companies likely have speculative-grade ratings, giving a boost to potential high-yield bond issuance. There's still clearly demand for such debt, which gained 0.9% in the first three trading days of the year alone, building on last year's 17.5% return. If the debt keeps rallying and yields keep falling, more of these companies will come back to the market.

3) The U.S. economy doesn't appear to be headed for a recession soon, meaning that investors will be more willing to keep lending to corporations. In fact, given the widely held belief that Treasury yields are going to be rising, some investors may prefer corporate bonds to government debt because corporate credit offers a cushion of extra yield to buffer from potential losses. This cushion of extra yield is still above the pre-crisis average.

Of course, the more debt these companies sell, the more pain there is to go around when the credit cycle does finally turn. But for now, the party's still in full swing, with the hangover just a distant prospect.

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