| Value | Category | Cases | |
|---|---|---|---|
| 1 | Direct from source | 1340 |
78.8%
|
| 2 | Covered container | 322 |
18.9%
|
| 3 | Uncovered container | 17 |
1%
|
| 8 | Unable to observe | 22 |
1.3%
|
| Sysmiss | 7807 |