| Value | Category | Cases | |
|---|---|---|---|
| 1 | Industrial activities | 3 |
0.1%
|
| 2 | Waste burning | 14 |
0.5%
|
| 3 | Transportation | 27 |
1%
|
| 4 | Construction | 7 |
0.3%
|
| 5 | Others | 22 |
0.8%
|
| Sysmiss | 2539 |