| Value | Category | Cases | |
|---|---|---|---|
| 0 | less than one year at level | 0 |
0%
|
| 1 | 1 |
0.7%
|
|
| 2 | 1 |
0.7%
|
|
| 3 | 43 |
31.2%
|
|
| 4 | 79 |
57.2%
|
|
| 5 | 5 |
3.6%
|
|
| 6 | 9 |
6.5%
|