The Environmental Protection Agency (EPA) has tracked the national trend in greenhouse gas emissions and removals since 1990. This website provides access to the reports they have created since then, and the reports represent the collaborative efforts of hundreds of experts from academic institutions, consultants, and other government agencies. Visitors can download the reports, or take a look at their respective executive summary. Each summary contains "an overview of recent trends, anthropogenic sources and sinks of greenhouse gases, and an explanation of the relative importance of emissions and removals from each source category." Users of the website are also encouraged to look over the overviews for different emissions, such as carbon dioxide and methane. The site is rounded out by a list of greenhouse gas inventories from other countries and global emission projections.