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2006 marked the end of Jigme Singye Wangchuck's reign as king of Bhutan. He had ascended to the throne in 1972 and implemented significant reforms, including the introduction of a democratic constitution and the establishment of a multi-party system. His abdication in 2006 paved the way for his son, Jigme Khesar Namgyel Wangchuck, to become the fifth king of Bhutan.