| Value | Category | Cases | |
|---|---|---|---|
| 0 | 116 |
3.1%
|
|
| 10 | 1 |
0%
|
|
| 1998 | 1 |
0%
|
|
| 2000 | 4 |
0.1%
|
|
| 2001 | 41 |
1.1%
|
|
| 2002 | 240 |
6.4%
|
|
| 2003 | 461 |
12.3%
|
|
| 2004 | 655 |
17.5%
|
|
| 2005 | 1168 |
31.3%
|
|
| 2006 | 407 |
10.9%
|
|
| 4444 | 7 |
0.2%
|
|
| 9998 | 11 |
0.3%
|
|
| 9999 | Missing | 621 |
16.6%
|
| Sysmiss | 18779 |