| Value | Category | Cases | |
|---|---|---|---|
| 0 | 452 |
94.6%
|
|
| 2000 | 1 |
0.2%
|
|
| 2002 | 1 |
0.2%
|
|
| 2003 | 1 |
0.2%
|
|
| 2004 | 1 |
0.2%
|
|
| 2005 | 3 |
0.6%
|
|
| 2006 | 2 |
0.4%
|
|
| 2007 | 1 |
0.2%
|
|
| 2008 | 3 |
0.6%
|
|
| 2009 | 3 |
0.6%
|
|
| 2010 | 8 |
1.7%
|
|
| 2011 | 2 |
0.4%
|
|
| Sysmiss | 2 |