Table:
|  |  | Year Ended December 31, |  |
| --- | --- | --- | --- |
|  | 2019 | 2018 | 2017 |
|  |  | (In millions) |  |
| Impairment, restructuring charges and other related closure costs | $(5) | $(21) | $(45) |
Paragraphs:
In 2019 we recorded $5 million of impairment, restructuring charges and other related closure costs, mainly consisting of impairment of equipment and licenses dedicated exclusively to certain development projects that were cancelled, while no alternative future use was identified internally.
In 2018 we recorded $21 million of impairment, restructuring charges and other related closure costs, consisting of: (i) $19 million related to the set-top box restructuring plan and (ii) $2 million of impairment of acquired technologies, for which it was determined that they had no future alternative use.
In 2017 we recorded $45 million of impairment, restructuring charges and other related closure costs, primarily consisting of: (i) $34 million of net restructuring charges related to the set-top box restructuring plan; (ii) $13 million of restructuring charges related to the restructuring plan in Bouskoura, Morocco;
(iii) $3 million charge relating to the update of the existing unused lease provision and (iv) $5 million income for the reversal of provisions related to previously announced restructuring plans, mainly the Embedded Processing Solutions business restructuring plan, for which accrued provisions were not fully used at completion of the plan.
Question:
What is the average Impairment, restructuring charges and other related closure costs?
Answer: (5+21+45) / 3 = 23.67