Table 1.
Response rates in the six surveys
| Survey year | Number | Response rate (%) |
|---|---|---|
| 1993/94 | 3584 | 85 |
| 1997/98 | 3802 | 90 |
| 2001/02 | 3926 | 87 |
| 2005/06 | 4421 | 85 |
| 2009/10 | 6880 | 88 |
| 2013/14 | 7867 | 69 |
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