| Value | Category | Cases | |
|---|---|---|---|
| 1 | Boiling | 32 |
1.3%
|
| 2 | Filtration | 1129 |
45.3%
|
| 3 | Chemical processing | 1177 |
47.2%
|
| 4 | Other | 157 |
6.3%
|
| Sysmiss | 9968 |