Swiss bee colonies, for example, have been shown to ensure “a yearly agricultural production worth about US$ 213 million by providing pollination,” and the value of an improved microclimate from 400,000 trees planted by local authorities in Canberra [Australia] has been estimated at between US$20 and US$67 million.

Goldin, Ian. The Butterfly Defect Princeton University Press. Kindle Edition. [location2644]