Last week's corporate bond issues topped $30 billion for only the second time since the Fed started taper talk in late May. Here's a summary of a few deals.

Sprint (NYSE:S) dialed up investors and raised a total of $6.5 billion with eight- and 10-year notes in a private placement. The coupon rates for the high-yield paper were 7.25% and 7.875%, respectively. That's nearly $500 million per year in debt service that Sprint needs to cover. According to the company's press release, the money will be used "for general corporate purposes, which may include, among other things, redemptions or service requirements of outstanding debt and network expansion and modernization." December 2016 was the earliest maturity I found for any Sprint bond issue, although there may be other debt planned for redemption. Let's hope the uses for the money can clear the big debt service hurdle.

Home Depot (NYSE:HD) is doing a little remodeling to its balance sheet with $3.25 billion spread over five-, 10.5-, and 30.5-year tranches with coupon rates ranging from 2.25% to 4.875%. Home Depot's press release says $1.25 billion will be used to redeem some 5.25% paper that matures in December and the other $2 billion will be used for share buybacks over and above previously announced plans. The combination of lower coupon rates and not paying dividends on $2 billion of shares means the debt service costs for the new issues are roughly the same as for the maturing 5.25% paper. No significant change to cash flow and about 2% of outstanding shares taken off the market sounds like a good deal for Home Depot shareholders.

Starbucks (NASDAQ:SBUX) brewed a grande-size deal with $750 million of 10-year 3.85% notes. The company's press release says the money is going toward "general corporate purposes, which may include business expansion, payment of cash dividends on Starbucks common stock, the repurchase of common stock under the company's ongoing share repurchase program, or financing of possible acquisitions." There are a couple of interesting points in this deal. First, Starbucks only had $550 million in long-term debt, so this deal more than doubles long-term debt. Next, Starbucks has plenty of earnings and cash flow to cover its dividend and a stock repurchase program. The company is expanding, particularly in China, and an acquisition is always a possibility. In short, this looks like a lot of new debt for a company that doesn't really need to borrow.

CME Group (NASDAQ:CME) made a market for its own debt, selling $750 million of 5.3% 30-year paper. The money will be used to redeem $750 million of 5.75% paper maturing next February. The refi will save CME a little more than $3 million per year in debt service.

Nabors (NYSE:NBR) drilled into the markets for $700 million split between three- and 10-year issues with 2.35% and 5.1% coupon rates, respectively. The driller is putting the money toward funding a tender offer for the company's 2019 9.25% notes. There's $1.125 billion of that paper outstanding and, if I did the math correctly, Nabors will be offering a bit more than a 25% premium to par value for the notes.

Comparing the rates Sprint had to pay to what the other four companies are paying highlights the importance of credit quality to borrowing costs. Sprint is paying a much higher coupon rate on its new eight-year than CME Group or Home Depot are paying on 30-year paper.