| Value | Category |
|---|---|
| 0 | Less than 1year |
| 1 | 01 year to less than 2 years |
| 2 | 2 years to less 3 years |
| 3 | 3 years to less than 4 years |
| 4 | 4 years to less than 5 years |
| 10 | 10 years to less than 11 years |
| 20 | 20 years to less than 21 years |
| 97 | 97 years to less than 98 years |
| 98 | 98 years and over |