| Value | Category | Cases | |
|---|---|---|---|
| 2003 | 6 |
0.3%
|
|
| 2004 | 309 |
12.9%
|
|
| 2005 | 389 |
16.2%
|
|
| 2006 | 464 |
19.4%
|
|
| 2007 | 516 |
21.6%
|
|
| 2008 | 651 |
27.2%
|
|
| 2009 | 21 |
0.9%
|
|
| 9997 | Inconsistent | 38 |
1.6%
|
| 9998 | DK | 0 |
0%
|
| Sysmiss | 20140 |