Table
| 2014 | Change in per cent | ||
|---|---|---|---|
| Since 1990 | 2013 - 2014 | ||
| 1Does not include international sea and air traffic. | |||
| Nitrogen oxides (NOX) | 142 | -26.2 | -7.3 |
| Sulphur dioxide (SO2) | 17 | -68.1 | -0.2 |
| Ammonia (NH3) | 26 | 6.4 | -1.9 |
| Non-methane volatile organic compounds (NMVOC) | 139 | -52.3 | 2.4 |
| Carbon monoxide (CO) | 244 | -67.4 | -7.8 |