Tropical rainforests receive average annual rainfall of 200–450 cm (2,000–4,500 mm), distributed relatively evenly throughout the year with no prolonged dry season. This high and consistent precipitation supports the world's most diverse terrestrial ecosystems. They are found within 10° north and south of the equator in the Amazon (South America), Congo Basin (Africa), and Southeast Asia/Indonesia. The minimum threshold for tropical rainforest classification is typically >200 cm/year.