Explain whether or not the impairment expense for software can be reversed.

17 INTANGIBLE ASSETS 2020 $M 2021 $M Accumulated Amortisation At Cost and Impairment 166 35 1,874 (1,394) Net Book Value 166 35 480 Accumulated Amortisation At Cost and Impairment 162 35 1,966 (1,281) Net Book Value 162 35 685 Goodwill Airport landing slots Software Brand names and trademarks Customer contracts/relationships Contract intangible assets Total intangible assets 1 1 1 1 4 (4) 4 171 (4) (4) (1,402) 167 167 849 167 2,335 2,251 (1,285) 1,050 Cash Additions Transfers? Amortisation Impairment Other Opening Net Book Value 162 35 Closing Net Book Value 166 4 2021 $M Goodwill Airport landing slots Software Brand names and trademarks Contract intangible assets Total intangible assets 35 480 14 1 (196) (22) (2) 685 1 1 167 3 1 167 3 17 (4) (200) 1,050 1 (22) 3 3 849 For the year ended 30 June 2021 Other Impairment (47) Closing Net Book Value 162 35 685 2 17 INTANGIBLE ASSETS (CONTINUED) 2020 Opening Net Cash $M Book Value Additions Transfers? Amortisation Goodwill 209 Airport landing slots 35 Software 826 150 1 (197) Brand names and trademarks 28 Customer contracts/relationships 1 Contract intangible assets 126 41 Total intangible assets 1,225 191 1 (197) 1. Additions includes capitalised interest of $6 million. 2. Transfers includes those between categories of intangible assets and transfers from/(to) other balance sheet accounts. (97) (26) 1 (1) (1) 167 (170) 1,050 For the year ended 30 June 2021 25 IMPAIRMENT OF ASSETS AND RELATED COSTS (CONTINUED) iv. Summary of Impairments and Liabilities recognised 2021 $M 2020 SM 155 1,087 23 3 Impairment of individual assets Impairment of A380s and onerous contractual commitments relating to A380s Impairment of 747s held for sale Impairment of software intangibles and onerous contractual commitments Impairment of property, plant and equipment and recognition of exit costs Total impairment of individual assets 97 33 7 47 198 1,254