1. Intertie Transactions Failure Working Group Tuesday April 19, 2005

2. 2 Agenda Introduction Summary of data Review of definitions Review of data Discussion and Next Steps

3. 3 Summary of Data Total Monthly Scheduling Deviation on all Interchanges –By Import/Export –By reason for scheduling deviation –By total monthly MWhs –As a percentage of Monthly Trade –By transaction count

4. 4 Summary of Data (Cont’d) Monthly Scheduling Deviation by Interchange: Michigan, Manitoba, Minnesota, TransEnergie (HQ), NYISO. –By Import/Export –By reason for scheduling deviation –By total monthly MWh –As a percentage of Monthly trade –By transaction count –By On-Peak Exports or Imports and Off-Peak Exports or Imports

5. 5 Summary of Data (Cont’d) Anonymous Participant Failure Rate from August 2003 to February 2005 for all interfaces –Expressed as a percentage of all scheduling deviations –Expresses as a percentage of the Participants total trade (similar calculation as guideline failure ratio)

6. 6 Definitions Pre-Dispatch Constrained Schedule (PDC). The final PDC schedules issued prior to the delivery hour. Dispatch Constrained Schedule (DC). DC schedules contain all transactions which began at the start of the delivery hour. Scheduling Deviation in MWhs = PDC schedules in MWhs – DC schedules in MWhs Percentage of Monthly Scheduling Deviation = Monthly Scheduling Deviation in MWhs / Monthly PDC schedules in MWhs

7. 7 Definitions - continued Percentage of Export Monthly Scheduling Deviation = Monthly Export Scheduling Deviation in MWhs / Monthly Export PDC schedules in MWhs Percentage of Import Monthly Scheduling Deviation = Monthly Imports Scheduling Deviation in MWhs / Monthly Import PDC schedules in MWhs By Interchange: Percentage of Total Monthly Scheduling Deviation = Monthly Scheduling Deviation in MWhs for Intertie / All Monthly PDC schedules in MWhs for the Intertie

8. 8 Definitions - continued By Interchange: Percentage of Monthly Export Scheduling Deviation = Monthly Export Scheduling Deviation in MWhs for Intertie / All Monthly Exports in MWhs for the Intertie Percentage of Monthly Import Scheduling Deviation = Monthly Import Scheduling Deviation in MWhs for Intertie / All Monthly Imports in MWhs for the Intertie Percentage of Monthly Export On-peak Scheduling Deviations = Monthly Scheduling Deviation for On-peak Exports in MWhs / Monthly PDC schedules for On-peak Exports in MWhs

9. 9 Definitions - continued Percentage of Monthly Export Off-peak Scheduling Deviations = Monthly Scheduling Deviation for Off-peak Exports in MWhs / Monthly PDC schedules for Off-peak Exports in MWhs Percentage of Monthly Import On-peak Scheduling Deviations = Monthly Scheduling Deviation for On-peak Imports in MWhs / Monthly PDC schedules for On-peak Imports in MWhs Percentage of Monthly Import Off-peak Scheduling Deviations = Monthly Scheduling Deviation for Off-peak Imports in MWhs / Monthly PDC schedules for Off-peak Imports in MWhs

10. 10 Definitions - continued Ratio 1 = MP(A) failures due to Tag or Economics in MWhs/ All MP(A) Scheduling deviations in MWhs Ratio 2 = MP(A) failures due to Tag or Economics/ All MP(A) Trade in MWhs –similar to guideline failure ratio