8. Other operating expenses
‘Other operating expenses’ include insurance, costs of office accommodation, fixtures and fittings, auditor’s fees, marketing costs, rental and lease costs for operating assets and additions to provisions.
Auditor’s fees
(in millions of euros) | 2018 | 2017 |
Statutory audits | 3.4 | 2.5 |
Other assurance engagements | 0.3 | 0.4 |
Tax advisory services | - | - |
Other services | - | - |
Total | 3.7 | 2.9 |
The auditor’s fees comprise the fees both for services in the Netherlands and those for the networks abroad.