| Day | Rate | Set date |
|---|---|---|
| 1 May | 18.8100 | .. |
| 2 May | 18.6800 | .. |
| 3 May | 17.9900 | .. |
| 4 May | 17.9800 | .. |
| 7 May | 18.2700 | .. |
| 8 May | 18.2800 | .. |
| 9 May | 18.9900 | .. |
| 10 May | 19.0200 | .. |
| 11 May | 18.9500 | .. |
| 14 May | 19.7100 | .. |
| 15 May | 19.5900 | .. |
| 16 May | 19.0300 | .. |
| 17 May | 18.8700 | .. |
| 18 May | 18.7600 | .. |
| 21 May | 18.2600 | .. |
| 22 May | 17.6800 | .. |
| 23 May | 17.6800 | .. |
| 24 May | 17.8300 | .. |
| 25 May | 17.8000 | .. |
| 29 May | 17.9800 | .. |
| 30 May | 18.0800 | .. |
| 31 May | 17.4000 | .. |