| Day | Rate | Set date |
|---|---|---|
| 1 May | 19.5700 | .. |
| 2 May | 19.4500 | .. |
| 3 May | 19.6600 | .. |
| 7 May | 19.9900 | .. |
| 8 May | 20.1400 | .. |
| 9 May | 20.1400 | .. |
| 10 May | 19.6000 | .. |
| 13 May | 19.2900 | .. |
| 14 May | 19.0600 | .. |
| 15 May | 19.1500 | .. |
| 16 May | 19.0600 | .. |
| 17 May | 19.5800 | .. |
| 20 May | 19.5700 | .. |
| 21 May | 19.3300 | .. |
| 22 May | 19.1300 | .. |
| 23 May | 19.2000 | .. |
| 24 May | 19.3500 | .. |
| 28 May | 19.4300 | .. |
| 29 May | 19.1600 | .. |
| 30 May | 19.3100 | .. |
| 31 May | 19.2100 | .. |