A change in an accounting estimate should be accounted for:

The effect of a change in an accounting estimate shall be recognised prospectively by including it in profit or loss in: [IAS8.36]

• the period of the change, if the change affects that period only, or
• the period of the change and future periods, if the change affects both.

However, to the extent that a change in an accounting estimate gives rise to changes in assets and liabilities, or relates to an item of equity, it is recognised by adjusting the carrying amount of the related asset, liability, or equity item in the period of the change. [IAS8.37]

the change in an accounting estimate shall be recognised prospectively