For the third straight year, strong returns from private market and international investments played an important role to help push the Core Retirement Fund to a 15.8% return in 2006 beating the 14.6% benchmark return. The Core Fund (formerly known as the Fixed Fund) is the larger of the two trust funds of the Wisconsin Retirement System (WRS) and has diversified holdings in domestic and international stocks, bonds, loans, real estate and private equity.