| Value | Category | Cases | |
|---|---|---|---|
| 1 | Before 1974 | 190 |
37.6%
|
| 2 | 1975-1984 | 44 |
8.7%
|
| 3 | 1985-1994 | 58 |
11.5%
|
| 4 | 1995-2004 | 110 |
21.8%
|
| 5 | 2005 and above | 103 |
20.4%
|