Tariffs Recent Filings PGA Summaries Iowa Electric Workshops Supplemental Information Electric Gas Btu Factors Cost of Gas Distribution Charges Energy Efficiency Exit Fees Firm Supply Standby Service Gas Retention Factors Imbalance Cashout Rates Imbalance Charges Interruptible Commodity Prices ISR Margin Manufactured Site Clean-Up RTP Illinois Rider 17 Customer Generation

Supplemental Information Gas: Imbalance Cashout Rates Navigator Imbalance Cashout Rates: 2008 - Monthly and Daily | 2007 - Monthly and Daily | 2006 - Monthly and Daily Select month and year below to view Daily Imbalance Cashout Rates. Rate Summary: 2006 Monthly and Daily Imbalance Cashout Rates Company Rates Supply Charges Transportation Charges (Mo/Yr) Pipeline Buy ($/Therm) Sell ($/Therm) Index Commodity ($/Therm) Commodity ($/Therm) Demand ($/Therm) Fuel (%) ACA ($/Therm) Surcharges ($/Therm) Jan 2006 ANR $0.79182 $0.81049 ANR-OK $0.74927 $0.00145 $0.01840 3.77% $0.00018 $0.00000 NGPL $0.78785 $0.80589 NGPL-MC $0.73966 $0.00146 $0.01777 4.52% $0.00018 $0.00000 NNG $0.80831 $0.84076 Demarcation $0.78006 $0.00376 $0.03198 1.60% $0.00000 $0.00000 Feb 2006 ANR $0.71242 $0.73083 ANR-OK $0.67398 $0.00145 $0.01814 3.77% $0.00018 $0.00000 NGPL $0.71727 $0.73557 NGPL-MC $0.67325 $0.00146 $0.01803 4.52% $0.00018 $0.00000 NNG $0.73404 $0.76848 Demarcation $0.70805 $0.00376 $0.03393 1.60% $0.00000 $0.00000 Mar 2006 ANR $0.62144 $0.64763 ANR-OK $0.58771 $0.00145 $0.02581 3.77% $0.00018 $0.00000 NGPL $0.62462 $0.63620 NGPL-MC $0.58608 $0.00146 $0.01141 4.52% $0.00018 $0.00000 NNG $0.63447 $0.64918 Demarcation $0.61150 $0.00376 $0.01450 1.60% $0.00000 $0.00000 Apr 2006 ANR $0.61056 $0.63135 ANR-OK $0.57752 $0.00145 $0.02048 3.75% $0.00018 $0.00000 NGPL $0.61779 $0.63439 NGPL-MC $0.58075 $0.00034 $0.01636 4.52% $0.00018 $0.00000 NNG $0.62752 $0.64053 Demarcation $0.60618 $0.00375 $0.01282 1.37% $0.00000 $0.00000 May 2006 ANR $0.55900 $0.58931 ANR-OK $0.52861 $0.00145 $0.02987 3.75% $0.00018 $0.00000 NGPL $0.56231 $0.56619 NGPL-MC $0.52855 $0.00034 $0.00383 4.52% $0.00018 $0.00000 NNG $0.56868 $0.57394 Demarcation $0.54900 $0.00375 $0.00518 1.37% $0.00000 $0.00000 June 2006 ANR $0.59132 $0.62139 ANR-OK $0.55927 $0.00145 $0.02963 3.75% $0.00018 $0.00000 NGPL $0.59416 $0.59540 NGPL-MC $0.55852 $0.00034 $0.00122 4.52% $0.00018 $0.00000 NNG $0.59670 $0.60170 Demarcation $0.57623 $0.00375 $0.00493 1.37% $0.00000 $0.00000 July 2006 ANR $0.58888 $0.61484 ANR-OK $0.55695 $0.00145 $0.02558 3.75% $0.00018 $0.00000 NGPL $0.59025 $0.61083 NGPL-MC $0.55484 $0.00034 $0.02028 4.52% $0.00018 $0.00000 NNG $0.59407 $0.59783 Demarcation $0.57368 $0.00375 $0.00371 1.37% $0.00000 $0.00000 Aug 2006 ANR $0.69865 $0.72535 ANR-OK $0.66106 $0.00145 $0.02631 3.75% $0.00018 $0.00000 NGPL $0.70351 $0.72043 NGPL-MC $0.66140 $0.00034 $0.01667 4.52% $0.00018 $0.00000 NNG $0.70855 $0.71177 Demarcation $0.68494 $0.00375 $0.00318 1.37% $0.00000 $0.00000 Sept 2006 ANR $0.46444 $0.48063 ANR-OK $0.44117 $0.00145 $0.01603 3.75% $0.00018 $0.00000 NGPL $0.46544 $0.46905 NGPL-MC $0.43963 $0.00034 $0.00357 4.52% $0.00018 $0.00000 NNG $0.48263 $0.48753 Demarcation $0.46775 $0.00375 $0.00485 1.37% $0.00000 $0.00000 Oct 2006 ANR $0.54150 $0.55651 ANR-OK $0.51465 $0.00145 $0.01486 3.75% $0.00016 $0.00000 NGPL $0.54417 $0.55048 NGPL-MC $0.51410 $0.00034 $0.00625 4.52% $0.00016 $0.00000 NNG $0.57399 $0.58098 Demarcation $0.55702 $0.00373 $0.00692 1.37% $0.00000 $0.00000 Nov 2006 ANR $0.63890 $0.65225 ANR-OK $0.60748 $0.00145 $0.01323 3.75% $0.00016 $0.00000 NGPL $0.64168 $0.66140 NGPL-MC $0.60522 $0.00146 $0.01953 4.52% $0.00016 $0.00000 NNG $0.67704 $0.72152 Demarcation $0.65652 $0.00376 $0.04405 1.54% $0.00000 $0.00000 Dec 2006 ANR $0.66400 $0.68741 ANR-OK $0.63142 $0.00145 $0.02318 3.75% $0.00016 $0.00000 NGPL $0.66860 $0.70607 NGPL-MC $0.63068 $0.00146 $0.03711 4.52% $0.00016 $0.00000 NNG $0.68282 $0.72427 Demarcation $0.66215 $0.00376 $0.04106 1.54% $0.00000 $0.00000 Note: Supply Commodity is the monthly average of the daily indices published in Gas Daily. Transportation Commodity is the weighted average demand of awarded capacity release postings. Navigator Imbalance Cashout Rates: 2008 - Monthly and Daily | 2007 - Monthly and Daily | 2006 - Monthly and Daily 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.