The carrying amount of deferred tax assets should be reviewed at each balance sheet date.
An enterprise should write-down the carrying amount of a deferred tax asset to the extent that it is no longer reasonably certain or virtually certain, as the case may be, that sufficient future taxable income will be available against which deferred tax asset can be realised. Any such write-down may be reversed to the extent that it becomes reasonably certain or virtually certain, as the case may be, that sufficient future taxable income will be available.