| Baseline | 6 month | 6 month change | 12 month | 12 month change | 18 month | 18 month change | 24 month | 24 month change | |
| All participants | 7.7 | 6.6 | -1.1 | 6.6 | -1.1 | 6.9 | -0.8 | 6.4 | -1.3 |
| <31 | 7.2 | 6.7 | -0.5 | 6.3 | -0.9 | 8.1 | 1.0 | 8.0 | 0.8 |
| 31-40 | 7.6 | 7.8 | 0.3 | 6.8 | -0.7 | 6.6 | -1.0 | 5.8 | -1.7 |
| 41-50 | 8.8 | 7.3 | -1.5 | 8.3 | -0.5 | 8.1 | -0.7 | 8.0 | -0.8 |
| 51-60 | 7.5 | 6.6 | -0.9 | 6.7 | -0.8 | 6.8 | -0.7 | 6.5 | -1.0 |
| 60+ | 7.5 | 6.6 | -0.8 | 6.4 | -1.1 | 6.7 | -0.8 | 5.9 | -1.5 |