Bond Markets Get Riskier

Bond markets are growing riskier as investors seeking steady returns bid up prices and ignore some early warning signs similar to those that flashed during the credit bubble.

The U.S. high-yield default rate fell to 5.1% in August from 13.2% a year ago, Moody's Investors Service reported recently, adding it expected the rate to fall to less than 3% by the end of the year.

Interest rates paid by companies with strong credit ratings have tumbled this year, falling to 1.8 percentage points above the yields on comparable U.S. Treasury bonds, which themselves are among the lowest yields in decades. Companies with weak credit ratings are paying 6.2 percentage points above Treasurys, down from nearly 20 percentage points in 2008, according to Barclays Capital indexes.

Treasurys have already seen their weaknesses exposed after a recent sell-off. Since the start of September, 10-year Treasurys have lost 2.2% and 30-year government bonds are down 6.9%, compared with a 5.6% gain for the Dow Jones Industrial Average.

The demand for bonds has allowed some of the riskiest borrowers to sell bonds with fewer protections for investors. These provisions, or covenants, prevent companies from taking actions that would hurt bondholders and would protect investors if companies are sold.