Japan has had nine short-lived prime ministers over the past 12 years since the late Noboru Takeshita was forced to resign in 1989, having only two serve for two years or longer.
That alone shows the period was one of the most turbulent in modern Japanese politics, one during which the nation's economy fell from the bubble boom to its worst postwar slump.
On Monday, the first trading day since Prime Minister Yoshiro Mori agreed Saturday to move up the date of the Liberal Democratic Party election -- a move widely taken to indicate his readiness to step down -- the Nikkei average on the Tokyo Stock Exchange closed at 12,171.37, compared with 33,667.42 at the end of Takeshita's administration.