During both terms of office he faced severe economic problems; repeated sterling crises led to devaluation in 1967, while he attempted unsuccessfully to deal with high inflation in 1974–76 by seeking an agreement with trade unions over limiting pay increases. His government introduced a number of social reforms, including reducing the voting age to 18, liberalizing the laws on divorce, homosexuality, and abortion, and introducing comprehensive schooling. Overseas, he was unable to persuade the regime of Ian Smith in Rhodesia (Zimbabwe) to back down over its declaration of independence (1965), and therefore introduced economic sanctions against Rhodesia. In 1974 Wilson renegotiated Britain’s terms of entry into the European Economic Community, confirming British membership after a referendum in 1975. He resigned as leader of the Labour Party the following year and was replaced as Prime Minister by James Callaghan.