| Value | Category | Cases | |
|---|---|---|---|
| 1995 | 1 |
1.4%
|
|
| 2000 | 1 |
1.4%
|
|
| 2001 | 1 |
1.4%
|
|
| 2002 | 2 |
2.8%
|
|
| 2004 | 1 |
1.4%
|
|
| 2005 | 1 |
1.4%
|
|
| 2007 | 3 |
4.2%
|
|
| 2008 | 27 |
38%
|
|
| 2009 | 28 |
39.4%
|
|
| 9999 | Yet to back | 6 |
8.5%
|
| Sysmiss | 235 |