The European Union air pollutant emission inventory report compiled by the European Environment Agency (EEA) shows that the EU-27 has cut sulphur oxides (SOx) emissions by 78% since 1990. The decline was particularly sharp during the latest reporting year, falling 20% in 2008 compared to 2007. The emissions of three ozone precursors � CO, NMVOCs and NOx � also continued the downward trend. The annual EU-27 emission inventory reported under the United Nations Economic Commission for Europe (UNECE) Long-range Transboundary Air Pollution (LRTAP) Convention confirms that emissions of most air pollutants continue to decline. SOx is an important air pollutant that acidifies ecosystems and forms harmful fine particulate matter in the atmosphere. Since the early 1990s a combination of measures has helped reduce emissions, including introducing low sulphur fuels and fitting pollution control equipment in European industrial facilities. Lower emissions from public power plants in Bulgaria, Poland and Spain contributed to the 20% annual emission reduction in 2008. Spain, for example, reduced its SOx emissions by using less coal to generate electricity and instead relying on natural gas and renewables such as wind, photovoltaics and biomass. CO, NMVOCs and NOx are main contributors to the formation of ground-level ozone, a harmful pollutant that can trigger respiratory problems, contribute to premature mortality and also damage plants, reducing agricultural crop yields. EU-27 emissions of these ozone precursors fell in 2008 in a number of member states, including France, Spain and UK, particularly from public power plants. Emissions from road transport also fell significantly in these member states, partly reflecting reduced freight transport on roads in the second half of 2008 due to economic recession.