UBS shares have experienced a significant decline of over 6% this week, despite the bank reporting strong fourth-quarter profits of $770 million and a full-year profit of $5.09 billion. Investor concerns about future capital requirements, particularly following the Credit Suisse takeover, have overshadowed positive earnings, leading to a 9% drop on the results day. Analysts remain optimistic, with over half recommending a buy, and Goldman Sachs setting a target price of 44.50 francs, suggesting a potential 47% increase in the medium term.