| Value | Category | Cases | |
|---|---|---|---|
| 2001 | 823 |
4.1%
|
|
| 2002 | 4110 |
20.7%
|
|
| 2003 | 4445 |
22.4%
|
|
| 2004 | 4481 |
22.6%
|
|
| 2005 | 4636 |
23.3%
|
|
| 2006 | 1349 |
6.8%
|
|
| 9997 | Inconsistent | 0 |
0%
|
| 9998 | DK | 23 |
0.1%
|
| 9999 | Missing | 3 |
0%
|
| Sysmiss | 2642 |