Table 2.
Descriptive statistics
| Variable | Mean |
|---|---|
| Individual demographic characteristics | |
| Male | 48% |
| Female | 52% |
| Average age at interview | 61.8 (5.5) |
| Health measures | |
| Death within 2 years | 2% |
| Disability (any ADL or IADL) | 25% |
| Any ADL | 10% |
| Any IADL | 21% |
| Diabetes | 12% |
| Heart condition | 17% |
| High blood pressure | 42% |
| Chronic lung disease | 10% |
| Major psychiatric condition | 13% |
| Stroke | 4% |
| Arthritis | 49% |
| BMI | 27.4 (5.2) |
| Height (inches) | 67.1 (4.1) |
| Socioeconomic factors | |
| Father worked in farming, forestry, or fishing | 18% |
| Father's years of schooling | 9.29 (3.79) |
| Mother's years of schooling | 9.70 (3.37) |
| Year and region of birth characteristics | |
| Crop yield residual | −.067 (.123) |
| Per capita personal income, 1983 dollars | 3,512 (1,244) |
| Employment index | 92 (11.7) |
| Births | 301,834 (114,476) |
| Infant deaths | 16,266 (6,254) |
| n | 56,162 |
Percentages are shown for dichotomous variables, and means with standard deviations in parentheses are shown for continuous variables. Those born in the first half of 1929 have no personal income data available for 1928. Disability questions asked in 1992 and 1994 are not consistent over time and are excluded. Consistent ADL measures are available for 1994–2004, whereas consistent IADL measures are available for 1996–2004. Two-year mortality is unavailable for 2004 because it is the most recent period of observation.