Please answer a question about the following article about Pope Paul VI:

Pope Paul VI (Latin: Paulus VI; Italian: Paolo VI), born Giovanni Battista Enrico Antonio Maria Montini (Italian pronunciation: [dʒioˈvani baˈtista enˈriko anˈtonjo marˈija monˈtini]; 26 September 1897 – 6 August 1978), reigned as Pope from 21 June 1963 to his death in 1978. Succeeding Pope John XXIII, he continued the Second Vatican Council which he closed in 1965, implementing its numerous reforms, and fostered improved ecumenical relations with Eastern Orthodox and Protestants, which resulted in many historic meetings and agreements. Montini served in the Vatican's Secretariat of State from 1922 to 1954. While in the Secretariat of State, Montini and Domenico Tardini were considered as the closest and most influential colleagues of Pope Pius XII, who in 1954 named him Archbishop of Milan, the largest Italian diocese. Montini automatically became the Secretary of the Italian Bishops Conference. John XXIII elevated him to the College of Cardinals in 1958, and after the death of John XXIII, Montini was considered one of his most likely successors.

In what year did Pope Paul VI close the Second Vatican Counsel?
1965