San Francisco, Calif. — International Business Machines Corp.’s (IBM) earnings have risen 8 percent in the latest quarter, resulting in IBM’s decision to raise its income guidance for the year.

Facing questions about whether the 100-year-old company’s efforts to link its mainframes with new businesses, services and software will sustain their profit increase, analysts still express concern that increased competition will impact the biggest parts of IBM’s services.

“Not many investors feel confident in jumping in on the long end,” said Rajeev Sharma, a money manager at First Investors Management Co., where he helps oversee $1.5 billion of investment-grade debt. “Rates are still expected to go up.”

The company also plans to sell $2 billion of five-year notes in an attempt to meet investor demands for shorter-term debt after Europe’s fiscal crisis and mounting concern that U.S. inflation will accelerate.

“They are spending faster than I thought — that is my main concern,” Yahoo reported Marshall said, adding that IBM’s ability to hit its long-term profit target is “not a slam dunk in my view.”

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