Bond yields in major developed countries declined sharply in mid-August, bringing the total amount of negative-yielding bonds around the globe to more than $16 trillion. The entire German yield curve is below zero. In the U.S., the 30-year Treasury yield fell below 2% for the first time in history, causing the yield spread between two-year/10-year Treasuries to invert briefly, for the first time since 2007. The three-month/10-year spread has been inverted on and off since March.
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