You will have an excess foreign tax credit for an income year if the amount of foreign tax you have paid is more than the Australian tax payable on that class of foreign income.
You may carry forward an excess foreign tax credit that arises in an income year for a class of foreign income for five years immediately following that income year. Your excess credit for a class of income may only be used where there is a credit shortfall for the same class of income in a later year. A credit shortfall will arise where the credit allowed for a class of foreign income for an income year is less than the Australian tax payable on that class of foreign income.
If you have incurred a loss for a class of foreign income, you cannot claim a tax credit in that year because the Australian tax payable on that class of income is nil. You may, however, carry forward the foreign tax credit relating to that class of income to subsequent years.