The Wall Street Journal reported that nonfinancial, corporate bond issues hit a record $29.7 billion last week. Let's see who's borrowing all that money and what they're doing with it.

Company

Amount Issued

Coupon Rate

Maturity

Aetna (NYSE: AET)

$500 million

4.13%

2021

Google (Nasdaq: GOOG)

$3.0 billion

1.25%-3.625%

2014-2021

Johnson & Johnson (NYSE: JNJ)

$4.4 billion

Floating – 4.85%

2013–2041

Kellogg's (NYSE: K)

$400 million

3.25%

2018

McDonald's (NYSE: MCD)

$400 million

3.63%

2021

Texas Instruments (NYSE: TXN)

$3.5 billion

Floating – 2.375%

2013-2016

Sources: Reuters and SEC filings.

Six companies accounted for about 40% of last week's corporate bond issue and the most common plan for the money among this group is paying off commercial paper.

Google, Johnson & Johnson, and Kellogg's plan on using the money to repay commercial paper. In each case, the company is paying off inexpensive commercial paper with higher-yielding debt. My Foolish colleague Rick Aristotle Munarriz raised the obvious question on Google's new debt -- why does a company with billions in cash need to hit the debt markets?

McDonald's doesn't say how it will use the money. Aetna will be paying off a maturing bond issue, and Texas Instruments plans to put the money toward its acquisition of National Semiconductor (NYSE: NSM). Separate from the bond issue, Aetna announced an increase in its share buyback program.

As a stock investor, it's easy to ignore the bond market, but a look at debt and how a company uses that money should be a part of Foolish investment research.

In a week with record corporate debt, at least three big firms are borrowing money to pay off less expensive commercial paper, and Aetna has arguably decided share buybacks are a better use of money than paying down debt. That looks like companies preparing for -- or at least protecting against -- climbing interest rates. Smart investors will join those CFOs and take a look at what higher interest rates would mean for their portfolios.

Are interest rates headed up soon or will cheap money be here for some time? Add your opinion with a comment below.

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