| Value | Category | Cases | |
|---|---|---|---|
| 99 | Missing | 2 |
0.2%
|
| 1997 | 1 |
0.1%
|
|
| 1998 | 1 |
0.1%
|
|
| 1999 | 1 |
0.1%
|
|
| 2000 | 7 |
0.7%
|
|
| 2001 | 6 |
0.6%
|
|
| 2002 | 9 |
0.8%
|
|
| 2003 | 5 |
0.5%
|
|
| 2004 | 16 |
1.5%
|
|
| 2005 | 15 |
1.4%
|
|
| 2006 | 13 |
1.2%
|
|
| 2007 | 29 |
2.7%
|
|
| 2008 | 41 |
3.8%
|
|
| 2009 | 66 |
6.1%
|
|
| 2010 | 120 |
11.2%
|
|
| 2011 | 174 |
16.2%
|
|
| 2012 | 457 |
42.5%
|
|
| 2013 | 112 |
10.4%
|
|
| Sysmiss | 650 |