Table:
|  | 2019 | 2018 | 2017 |
| --- | --- | --- | --- |
|  | €m | €m | €m |
| Parent company | 2 | 2 | 2 |
| Subsidiaries | 14 | 14 | 13 |
| Subsidiaries – new accounting standards1 | 1 | 5 | 1 |
| Audit fees: | 17 | 21 | 16 |
| Audit-related fees2 | 2 | 5 | 4 |
| Non-audit fees: | 2 | 5 | 4 |
| Total fees | 19 | 26 | 20 |
Paragraphs:
The total remuneration of the Group’s auditors, PricewaterhouseCoopers LLP and other member firms of PricewaterhouseCoopers International Limited, for services provided to the Group during the year ended 31 March 2019 is analysed below
Notes: 1 Fees during the implementation phase of new accounting standards, notably preparations for IFRS 15 “Revenue from Contracts with Customers” in the year ended 31 March 2018 and preparations for IFRS 16 “Leases” in the year ended 31 March 2019.
2 Relates to fees for statutory and regulatory filings during the year. In addition, the amount for the year ended 31 March 2018 includes non-recurring fees that were incurred during the preparations for a potential IPO of Vodafone New Zealand and the merger of Vodafone India and Idea Cellular. The amount for the year ended 31 March 2017 primarily arose from work on regulatory filings prepared in anticipation of a potential IPO of Vodafone India that was under consideration prior to the agreement for the merger of Vodafone India and Idea Cellular.
A description of the work performed by the Audit and Risk Committee in order to safeguard auditor independence when non-audit services are provided is set out in the Audit and Risk Committee report on pages 71 to 76.
Question:
What is the difference between the average audit fees and the average total fees for 2018 and 2019?
Answer: [(17+21)/2] - [(19+26)/2] = -3.5