Pay and bonuses in investment banking at Credit Suisse First Boston are running at their highest level as a proportion of revenues since Allen Wheat was ousted as chief executive three years ago.

Latest figures show that John Mack, who departed as chief executive last month after a 36-month campaign to cut costs and rescue the Swiss-American investment bank from losses, may not have solved its cost problem. Brady Dougan, his successor, faces a tough job to keep costs under control.