It introduced 12 management categories of protected areas, divided into two groups: strict protection areas, with the primary objective of biodiversity conservation, and sustainable use areas, which permit human settlement and natural resource use in accordance with sustainable management plans. In 2006, the MMA set up the National Register of Protected Areas (CNUC), a database collecting a wide range of biodiversity and management data for each official protected area, although information is often incomplete. In March 2015, 1 940 protected areas covered 17.2% of Brazil’s terrestrial area and inland waters.