Table
| 2014 | Change in per cent | ||
|---|---|---|---|
| Since 1990 | 2013 - 2014 | ||
| 1Does not include international sea and air traffic. | |||
| Nitrogen oxides (NOX) | 148 | -23.0 | -5.4 |
| Sulphur dioxide (SO2) | 17 | -68.1 | -2.4 |
| Ammonia (NH3) | 27 | 10.0 | -1.7 |
| Non-methane volatile organic compounds (NMVOC) | 140 | -52.0 | 3.7 |
| Carbon monoxide (CO) | 247 | -66.9 | -5.6 |