| Value | Category | Cases | |
|---|---|---|---|
| 1 | Less than a year | 818 |
36.2%
|
| 2 | 1 year to less than 3 years | 1051 |
46.5%
|
| 3 | 3 years or more | 356 |
15.8%
|
| 9 | Unspecified | 35 |
1.5%
|
| Sysmiss | 64226 |