UPDATE 1-State Street data still unnerves investors

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By Svea Herbst-Bayliss

BOSTON, May 13 (Reuters) - Financial services group State Street Corp (STT.N: Quote, Profile, Research, Stock Buzz) said on Tuesday that unrealized losses on its investment portfolio are nearly unchanged, but the news sent its shares down as investors hoped for a smaller number.

The company, one of the world's biggest institutional asset managers with $2 trillion in assets under management, told analysts for the second time in about a month it faces $1.9 billion in unrealized losses on its investment portfolio.

The company's share price was down 4.45 percent, or $3.32, at $71.35 in afternoon trading. Two competitors, Bank of New York Mellon and Northern Trust, suffered far smaller losses and the overall market was off slightly.

"The unrealized loss is about the same," State Street Chief Financial Officer Ed Resch told analysts at the UBS conference in New York.

While the company benefited as credit spreads came in during April and that helped to shrink the total unrealized losses, Resch said this was offset as the Treasury market backed up.

Executives did not present more bad news, but they also did not offer signs of any speedy improvement, which likely unnerved investors, industry analysts said.

"I think what might have investors spooked is that this is not a simple problem to fix," RBC Capital analyst Gerard Cassidy said.