Marsh produced underlying revenue growth of 4% with all major geographies contributing. This was driven by higher client retention rates and new business development. Guy Carpenter also produced impressive results in 2011. Underlying revenue growth was 5% driven both ongoing revenue and new business development and higher retention rates. This was a milestone year for Carpenter as well as revenue exceeded $1 billion for the first time.
The Consulting segment also delivered an impressive performance. Revenue grew 9% with underlying growth of 5%. Adjusted operating income rose 12% and the segment margin improved as well. Mercer produced underlying revenue growth of 4% and Oliver Wyman's growth was 7% for the second straight year.
So in summary, throughout Marsh & McLennan last year, we saw revenue increases and higher levels of profitability. We are very pleased with this performance, which confirms the investment case we articulated at Investor Day in September 2010. We generated organic growth and adjusted operating income of 12%. Growth in adjusted EPS was 13%, excluding the early debt retirement and these are the earnings from which we plan to grow this coming year. Our dividend yield averaged 3%. We maintained low capital requirements. We generated high levels of cash and we made progress on lowering the company's risk profile. As we move forward, we remain committed to focusing on profitable growth and prudent deployment of our excess cash flow in order to produce outstanding long-term returns for our shareholders.