Treasuries fall after disappointing 30-year auction

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NEW YORK (CNNMoney) -- Treasury prices fell Thursday after a disappointing sale of $16 billion of 30-years bonds.

"It was a relatively disappointing long bond option," Guy LeBas, Chief Fixed Income Strategist, Janney Montgomery Scott said. "Demand was lowest it's been since November."

It's been a big week for auctions.

The Treasury Department sold $32 billion of 3-year notes Tuesday and $24 billion of 10-year notes on Wednesday. Thursday's auction ended the Treasury's $72 billion refunding this week.

Ahead of the auction, investors were parsing through a deluge of economic data: weekly claims for unemployment benefits, retail sales, and producer prices.

Recently, mixed economic data as well as investors fearing the end of QE2 have weighed on the market.

The yield on the benchmark 10-year Treasury note edged up to 3.2%. Just a couple of weeks ago, the 10-year yield was hovering around 3.6%.

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"Since mid-March or before, there's this whole fear that the recovery is slowing down," Action Economics Fixed income analyst Kim Rupert said.

Rupert attributes rising commodity prices and fear that the Fed will let the QE2 expire as well as ongoing concerns over Greece and Portugal as factors weighing on investors.

QE2 or "quantitative easing" program is the central bank's program aimed at spurring economic growth by flooding the system with liquidity.

Treasuries are considered a safe-haven in times of economic uncertainty.

The 30-year yield rose to 4.4%, the 5-year yield ticked up to 1.88%, and the 2-year note was at 0.56%. Bond prices and yields move in opposite directions.