| Value | Category | Cases | |
|---|---|---|---|
| -99 | DK | 0 |
0%
|
| -88 | Missing | 0 |
0%
|
| -77 | NA | 0 |
0%
|
| 199 | 1 |
0.1%
|
|
| 1963 | 1 |
0.1%
|
|
| 1978 | 1 |
0.1%
|
|
| 1981 | 1 |
0.1%
|
|
| 1986 | 2 |
0.1%
|
|
| 1987 | 4 |
0.2%
|
|
| 1988 | 3 |
0.2%
|
|
| 1989 | 1 |
0.1%
|
|
| 1990 | 1 |
0.1%
|
|
| 1991 | 5 |
0.3%
|
|
| 1992 | 8 |
0.4%
|
|
| 1993 | 5 |
0.3%
|
|
| 1994 | 4 |
0.2%
|
|
| 1995 | 9 |
0.5%
|
|
| 1996 | 122 |
6.2%
|
|
| 1997 | 394 |
20.1%
|
|
| 1998 | 354 |
18.1%
|
|
| 1999 | 354 |
18.1%
|
|
| 2000 | 386 |
19.7%
|
|
| 2001 | 301 |
15.4%
|
|
| Sysmiss | 3 |