| 1991 | 1993§ | 1997* | 2005 | ||||
---|---|---|---|---|---|---|---|---|
 | M | F | M | F | M | F | M | F |
Number listed (N) | 708 | 799 | 414 | 635 | 533 | 596 | 852 | 1241 |
Mean age (SD) | 25.6 (7.5) | 26.4 (7.8) | 26.6 (8.4) | 27.8 (8.3) | 23.2 (8.1) | 24.5 (8.0) | 28.5 (8.6) | 28.1 (7.6) |
Participants (n) | 516 | 636 | 318 | 491 | 403 | 492 | 614 | 914 |
Mean age (SD) (all participants) | 25.7 (8.3) | 26.3 (8.0) | 26.5 (8.6) | 28.0 (8.6) | 22.5 (7.0) | 24.1 (7.3) | 28.7 (8.8) | 27.9 (8.6) |
†Mean age (SD) (participants aged 15–36 years) | 23.2 (6.0) | 23.1 (6.3) | 23.4 (6.0) | 23.0 (6.1) | 23.3 (7.0) | 23.2 (7.3) | 23.5 (6.6) | 23.4 (6.1) |
Participation rate (%) | 73.0 | 79.5 | 76.9 | 76.9 | 75.6 | 82.6 | 72.1 | 73.7 |