is no report available about his illness, as the papers have been moved to an unknown location, but it is commonly believed that he suffered from vascular dementia, probably due to atherosclerosis. Kekkonen withdrew from politics during his final years. He died at Tamminiemi on August 31, 1986, three days before his 86th birthday, and was buried with full honours. His heirs restricted access to his diaries and later an "authorised" biography by Juhani Suomi was commissioned, the author subsequently defending the interpretation of the history therein and denigrating most other interpretations. Critics have questioned the value of this work; the historian Hannu Rautkallio considered the biography little else than a "commercial project" designed for selling books rather than aiming for historical accuracy. Legacy Some of Kekkonen's actions remain controversial in modern Finland, and disputes continue about how to interpret many of his policies and actions. He often used what was termed the "Moscow card" when his authority was threatened, but he was not the only Finnish politician with close relations to Soviet representatives. Kekkonen's authoritarian behavior during his presidential term was one of the main reasons for the reforms of the Finnish Constitution in 1984–2003. Under these, the powers of Parliament and the prime minister were increased at the expense of presidential power. Several of the changes were initiated by Kekkonen's successors. Presidential tenure was limited to two consecutive terms. The President's role in cabinet formation was restricted. The President was to be elected directly, not by an electoral college. The President could no longer dissolve Parliament without the support of the Prime Minister. The Prime Minister's role in shaping the foreign relations of Finland was enhanced. Although controversial, his policy of neutrality allowed trade with both the Communist and Western blocs. The bilateral trade policy with the Soviet Union was lucrative for many Finnish businesses. His term saw a period of high sustained economic growth and increasing integration with the West. He negotiated entrance into EFTA and thus was an early beginner for Finnish participation in European integration, which later culminated in full membership in the EU and the euro. He remained highly popular during his term, even though such a profile approached that of a personality cult towards the end of his term. He is still popular among many of his contemporaries, particularly in his own Centre Party. Cabinets Kekkonen I Cabinet Kekkonen II Cabinet Kekkonen III