| Value | Category | Cases | |
|---|---|---|---|
| 1 | Natural Wall | 15 |
2.5%
|
| 2 | Rudimentary Wall | 167 |
27.9%
|
| 3 | Finished Wall | 274 |
45.8%
|
| 4 | 25 |
4.2%
|
|
| 5 | Missing | 117 |
19.6%
|
| Sysmiss | 1 |