| Value | Category | Cases | |
|---|---|---|---|
| 1 | Less than 1 year | 90 |
4.5%
|
| 2 | More than 1 year, and less than 2 years | 137 |
6.9%
|
| 3 | More than 2 years and less than 5 years | 517 |
25.9%
|
| 4 | More than 5 years | 1250 |
62.7%
|
| Sysmiss | 6 |