U.S. Treasurys were mostly flat on Friday as the 30-year long bond again surrendered price gains following an unexpectedly costly $16 billion government auction of new 30-year debt.
Yields on 30-year bonds, which have been favored in recent months by pension fund buyers, stood at 3.47 percent, reflecting a price loss of 9/32 on Friday.
A week ago, the yields on 30-year bonds touched a low of 3.34 percent that had not been seen since June 19 last year.
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"There's a little bit of profit-taking," said Kim Rupert, managing director at Action Economics in San Francisco. "The 30-year is near its most expensive for the year, and there's probably overhang from yesterday's auction. That was a little sour."