World Water Day has been observed on 22 March since 1993 when the United Nations General Assembly declared 22 March as "World Day for Water". This day was first formally proposed in Agenda 21 of the 1992 United Nations Conference on Environment and Development in Rio de Janeiro, Brazil. Observance began in 1993 and has grown significantly ever since; for the general public to show support, it is encouraged for the public to not use their taps throughout the whole day. The day has also become a popular Facebook trend. The UN and its member nations devote this day to implementing UN recommendations and promoting concrete activities within their countries regarding the world's water resources. Each year, one of various UN agencies involved in water issues takes the lead in promoting and coordinating international activities for World Water Day. Since its inception in 2003, UN-Water has been responsible for selecting the theme, messages and lead UN agency for the World Day for Water.