After Campbell's surprise resignation, there was speculation as to who would run.
The company has said little about the surprise resignation, except to describe the reason for it as personal.
The action came after the surprise resignation of Brazil's central bank president and a week of declines in the stock market, the most recent ones severe.
Hancock governed until his surprise resignation on January 29, 1785.
Steve Bracks held the seat from a by-election in 1994 until his surprise resignation on 30 July 2007.
News reports at the time suggested that his surprise resignation from the Senate came partly because he stood no immediate chance of becoming governor.
Wilson took over after the surprise resignation of promotion winning Nobby Clark.
After Mr. Wilson's surprise resignation in 1976, she might well have become party leader and the first woman to serve as prime minister.
July, 2012, saw the surprise resignation of the prime minister, Gilbert Houngbo.
The changes came after the surprise resignation of Brian Tobin, the industry minister.