| Value | Category | Cases | |
|---|---|---|---|
| 1 | Two years or less | 2289 |
23.3%
|
| 2 | Three to five years | 2402 |
24.4%
|
| 3 | More than five years | 4879 |
49.6%
|
| 4 | Don't know | 269 |
2.7%
|
| Sysmiss | 5218 |