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Notes to the Consolidated Financial Statements 

(Tabular amounts in millions of Canadian dollars, except share and per share amounts) 

## 3. Use of judgments and estimates, continued: 

## Key sources of estimation uncertainty, continued 

## Decommissioning and other provisions 

Measurement of the Company’s provisions and the related change in discount rate require the use of estimates with respect to the amount and timing of asset retirements, the extent of site remediation required and related future cash flows for the decommissioning provisions and estimates of expected customer renewals for the Company’s other provisions. The key assumptions used in determining these provisions are provided in note 23. 

## Income taxes 

Income taxes are determined based on estimates of the Company’s current income taxes and estimates of deferred income taxes resulting from temporary tax differences. Deferred income tax assets are assessed to determine the likelihood that they will be realized from future taxable income. Details of tax losses expected to be utilized and the basis of utilization are provided in note 17. 

## Revenue recognition 

As noted in note 2(f), estimates of the value of electricity and natural gas consumed by customers but not billed until subsequent to period-end are based on volume data provided by the parties responsible for delivering the commodity and contracted prices. 

Actual results may differ from these estimates. Adjustments to previous estimates, which may be material, will be recorded in the period they become known. 

## 4. Expenses: 

<img src='content_image/199052.jpg'>

