| Value | Category | Cases | |
|---|---|---|---|
| -1 | Missing | 0 |
0%
|
| 1 | Impassable | 8 |
0.7%
|
| 2 | Very poor | 120 |
10%
|
| 3 | Poor | 240 |
20%
|
| 4 | Fair | 230 |
19.2%
|
| 5 | Good | 522 |
43.5%
|
| 6 | Very good | 80 |
6.7%
|