In 2009, nature protected areas, which include designated nature protected areas, Natura 2000 sites as well as areas that fulfil the conditions for Natura 2000 sites, covered 39.7% of the Slovenian territory, which is nearly six times as much as in 1992. The surface area has increased mostly owing to Natura 2000 sites being designated in 2004, while in 2008 the increase was a consequence of the designation of those areas which, according to the European Commission, fulfil the conditions for Special Protected Areas, but had not been defined as Natura sites.