| Value | Category | Cases | |
|---|---|---|---|
| 1 | Less than a year | 81 |
10.1%
|
| 2 | 1-3 years | 248 |
30.9%
|
| 3 | 3-5 years | 142 |
17.7%
|
| 4 | Longer than 5 years | 301 |
37.5%
|
| 5 | Don't remember | 31 |
3.9%
|
| Sysmiss | 5347 |