| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 |
0%
|
| 1 | Impassable | 40 |
2.5%
|
| 2 | Very poor | 224 |
14%
|
| 3 | Poor | 358 |
22.4%
|
| 4 | Fair | 456 |
28.5%
|
| 5 | Good | 409 |
25.6%
|
| 6 | Very good | 112 |
7%
|