"You may have heard this from others as well, but it's true. You tell me where Bunds are going to go and I'll tell where Treasurys are going to go," Goncalves said.
In afternoon trading, U.S. 30-year Treasurys were last up more than a point in price to yield 3.04 percent, from a yield of 3.104 percent late Wednesday. Thirty-year bond yields earlier hit their highest since October at 3.159 percent.
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U.S. 10-year note yields, meanwhile, fell to 2.31 percent, from a yield of 2.368 percent late on Wednesday. Ten-year yields earlier on Thursday touched an eight-month peak of 2.425 percent.
A report showing initial claims for unemployment benefits falling to 276,000 for the week ended May 30. It was the 13th straight week that claims held below the 300,000 threshold. The data initially boosted yields.
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But that positive labor report was offset by data showing U.S. non-farm productivity fell more sharply than initially thought in the first quarter, leading to a jump in labor-related production costs.
The net effect on Treasuries was muted, as a result.