Milliman Inc. released its 2010 Group Health Insurance Survey, projecting that average January 2010 health insurance premium increases of 10.2 percent for Health Maintenance Organizations (HMOs) and 11.7 percent for Preferred Provider Organizations (PPOs).  Milliman officials say their survey is unique because it controls for changes to health plan design, shifts in premium cost sharing, and member demographics. 

From the executive summary:  

Milliman's 2010 Group Health Insurance Survey reports information on the nation's HMOs and fully insured PPOs that serve the commercial large- or mid-group markets. Milliman's survey provides a unique perspective in that it asks HMOs and PPOs to respond regarding a given set of group health benefits and demographics. The survey removes three important factors that can skew the results presented in other health cost surveys: changes in plan design, shifts in premium sharing between employer and employee, and member demographics. This perspective allows for easy comparisons among different areas of the country as well as comparisons between the years shown in the survey. Companies use the survey results to benchmark their financials to the competition and to explore expansion into neighboring markets. 

To purchase the survey: 2010 Group Health Insurance Survey 

Milliman, Inc. (2010). 2010 group health insurance survey.