Citigroup Inc. may slump below $30 a share, a drop of 14 percent, as U.S. bank shares extend declines on writedowns that will have a ``severe impact'' on their capital ratios, according to CIBC World Markets Inc. Meredith Whitney, the New York-based analyst who on Nov. 1 triggered a 2.6 percent slide in the Standard & Poor's 500 Index after saying Citigroup may cut its dividend, reduced her recommendation on the biggest U.S. banks to ``underweight'' from ``market weight,'' relative to the S&P 500. ``The optics for the group are not good at the moment, but they are poised to get worse,'' Whitney and Carla Krawiec, also based in New York, wrote in a report to investors today. ``We expect Tier 1 ratios to drop materially in the fourth quarter.'' Among the group of large-capitalization banks covered by CIBC, the analysts have a ``sector underperformer'' recommendation on Citigroup, and ``sector performer'' ratings on Charlotte, North Carolina-based Bank of America Corp. and Wachovia Corp. They have ``sector outperformer'' ratings on JPMorgan Chase & Co. and San Francisco-based Wells Fargo & Co. Citigroup's stock had its steepest retreat since 2002 on Nov. 1 after Whitney said the largest U.S. bank would have to cut its payout or sell assets to make up for losses. The analyst today forecast further declines for Citigroup, saying it may fall ``below $30.'' Thanks Meredith - without you, we would not have an objective observer! Hum...CIBC - anybody any idea how they are rated ????