context: The Paloki power plant is a hydroelectric power plant built by Outokumpu Oy in Heinävesi, Palokinkoski, located between Juojärvi and Varisvesi. The power plant was completed in 1961. Its waterfall is 19.4 meters and its output is 6.4 MW. [1] Later the owner was Imatran Voima Oy (Fortum). Today the plant is owned by Pohjois-Karjalan Sähkö Oy.
question: When was Outokumpu Oy's Paloki hydropower plant built?
answers.text: 1961