Lohmann has presided over Converium ever since the company's formation following a spin-off from Zurich Financial Services in 2001. However, over the last 12 months Converium has endured considerable hardship. In July 2004 Lohmann was forced to reveal that the company had to add as much as $400 million to reserves for prior years' claims. Converium's shares lost over half their value and the reinsurer closed its US operations. In making the announcement, the chairman of the board of directors, Peter Colombo, stated that: "the board believes that a management change is necessary to bring about a long-term cultural transformation and restore stakeholder confidence in the company". Mr Clarke, who has been a member of the Converium's board since 2002 and was appointed managing director in September 2004, said that the focus was now on "rebuilding the long-term value of Converium's franchise and the creation of a leaner structure". Last week, Converium was boosted by the news that it was able to renew 63% of its nonlife treaty business, representing about $1.24 billion in premiums.