Table 1. Sizes of the modelled population compartments by age and risk group averaged over the period of the study.
| Modelled Population | Age Group | ||||||
| 1 y | 1–4 y | 5–14 y | 15–24 y | 25–44 y | 45–64 y | 65+ y | |
| Average age group size (2003–2008) | 623,779 | 2,525,322 | 6,608,728 | 6,603,485 | 15,214,371 | 12,578,021 | 8,423,248 |
| Percent at high risk | 2.1% | 5.5% | 9.8% | 8.7% | 9.2% | 18.3% | 45.0% |
| Proportion at high risk, from RCGP surveya | 723/33,780 | 15,837/287,075 | 77,197/783,844 | 63,206/724,292 | 165,827/1,803,008 | 301,562/1,647,783 | 456,654/1,013,979 |
a
Number of individuals at high risk of complications associated with influenza/total number of individuals surveyed.