| Value | Category | Cases | |
|---|---|---|---|
| 1 | First year | 1799 |
27.3%
|
| 2 | Second year | 2192 |
33.3%
|
| 3 | Third year | 2513 |
38.1%
|
| 4 | Fourth year | 85 |
1.3%
|
| Sysmiss | 163 |