The most important rivers are Paraguay, which crosses the country, and Paraná, on the border with Brazil and Argentina. Along the river Paraná, in 1984, was built in ownership between Paraguay and Brazil, the colossal Itaipú dam, which is the largest operational hydroelectric power plant in the world. Another large hydroelectric power plant, always along the Paraná, is that of Yacyretá, and it's jointly owned between Paraguay and Argentina. Paraguay, thanks to these power stations, is the first exporter of hydropower in the world (in 2003 it produced 51.29 billion kWh and it has exported 44.17 billion kWh). The economy of the country is mainly linked to agriculture, are cultivate cotton, cassava, maize, rice, wheat, tobacco, sugar cane, sweet potatoes, beans, soya, coffee and fruits (oranges, bananas and pineapple). Very important are mainly cattle farming, but also pork, and the exploitation of forests (cedar, mahogany and walnut).