| Value | Category | Cases | |
|---|---|---|---|
| 1999 | 4 |
0.5%
|
|
| 2000 | 47 |
5.5%
|
|
| 2001 | 46 |
5.4%
|
|
| 2002 | 94 |
11%
|
|
| 2003 | 147 |
17.3%
|
|
| 2004 | 241 |
28.3%
|
|
| 2005 | 236 |
27.7%
|
|
| 2006 | 37 |
4.3%
|
|
| Sysmiss | 7282 |