After the constitutional changes of 1974, Tito began reducing his role in the day-to-day running of the state. He continued to travel abroad and receive foreign visitors, going to Beijing in 1977 and reconciling with a Chinese leadership that had once branded him a revisionist. In turn, Chairman Hua Guofeng visited Yugoslavia in 1979. In 1978, Tito traveled to the U.S. During the visit strict security was imposed in Washington, D.C. owing to protests by anti-communist Croat, Serb and Albanian groups.
In what year did Tito travel to the U.S. to visit Washington D.C., amist protest by anti-communist Croat, Serb and Albanian groups?
{'text': '1978', 'answer_start': 340}