| Day | Rate | Set date |
|---|---|---|
| 1 May | 17.2500 | .. |
| 2 May | 17.1900 | .. |
| 3 May | 16.5400 | .. |
| 4 May | 16.3300 | .. |
| 8 May | 16.7000 | .. |
| 9 May | 17.3300 | .. |
| 10 May | 17.3300 | .. |
| 11 May | 17.6000 | .. |
| 14 May | 18.1000 | .. |
| 15 May | 17.9100 | .. |
| 16 May | 17.7600 | .. |
| 17 May | 17.7700 | .. |
| 18 May | 17.6900 | .. |
| 21 May | 17.4100 | .. |
| 22 May | 17.2300 | .. |
| 23 May | 16.7500 | .. |
| 24 May | 16.6100 | .. |
| 25 May | 16.5200 | .. |
| 29 May | 16.6500 | .. |
| 30 May | 16.7500 | .. |
| 31 May | 16.2400 | .. |