| 1993 sample | 1996 sample | 1999 sample | 2003 sample | 2007 sample |
---|---|---|---|---|---|
N = 2897 | N = 2370 | N = 2032 | N = 1447 | N = 978 | |
% or mean (SD) | % or mean (SD) | % or mean (SD) | % or mean (SD) | % or mean (SD) | |
Adult SES | Â | Â | Â | Â | Â |
 Low | 61.65 | 61.10 | 59.94 | 58.12 | 57.67 |
 Median | 15.67 | 15.91 | 15.45 | 14.86 | 14.72 |
 High | 22.68 | 23.00 | 24.61 | 27.02 | 27.61 |
Gender | Â | Â | Â | Â | Â |
 Male | 42.94 | 43.80 | 44.49 | 45.34 | 46.93 |
 Female | 57.06 | 56.20 | 55.51 | 54.66 | 53.07 |
Age | 71.04 (5.65) | 73.29 (5.10) | 75.84 (4.85) | 78.80 (4.06) | 82.25 (3.73) |
Cognitive functioning (0–5) | 4.34 (1.09) | 4.39 (1.03) | 4.32 (1.08) | 4.11 (1.16) | 3.91 (1.27) |
Psychological distress (CES-D) | Â | Â | Â | Â | Â |
 Negative Affect (0–24) | 3.93 (4.96) | 4.26 (5.24) | 4.27 (5.34) | 3.79 (4.94) | 4.11 (4.93) |
 Lack of Positive Affect (0–6) | 2.81 (2.49) | 2.28 (2.42) | 2.12 (2.24) | 2.07 (2.24) | 1.79 (2.06) |