In the credit crisis, there is uncertainty and then there is complete guesswork. In the case of Marshall & Ilsley, analysts appear to have plumped for the latter.

No one can blame them for being off by 20% or 30% in this environment. But while Wall Street analysts' consensus estimate was a fourth-quarter profit of seven cents a share, according to Thomson Reuters, the Wisconsin financial-services company's actual result was in a totally different ballpark -- a loss of $1.55 a share.

The reason: hefty credit losses in construction and commercial portfolios.

With shocks like that, no wonder investors have lost faith in even the biggest institutions. Just look at Bank of America's plunge as investors guess the size of the hit it will have to take after the acquisition of Merrill Lynch. And how generous the government will be in filling the hole.