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Supplemental Information Gas: Gas Retention Factors All Jurisdictions Illinois - Iowa - Nebraska - South Dakota Effective Date (Month/Year) Retention (-%-) September 1995 1.27% October 1996 1.31% September 1997 1.09% September 1998 0.98% September 1999 1.46% September 2000 1.35% September 2001 0.62% September 2002 1.85% September 2003 1.49% September 2004 1.35% September 2005 1.46% September 2006 0.96% September 2007 1.24% September 2008 1.17% For Your Home | For Your Business | Safety | Rates | Energy Efficiency | Economic Development | Environmental Efforts About Us | Careers | News Room | Storm Center | Wind Energy | Contact | Streetlight Repair Request | System Outage Watch | Energy Choice | For Contractors | For Landlords | ©2008 MidAmerican Energy Holdings Company. All rights reserved.