Submitted on: 29 April 2008.
Revised on: 10 May 2008.
Accepted on: 24 May 2008.
Scandinavian Actuarial Journal
Submitted on: 09 November 2011.
Revised on: 01 December 2011.
Accepted on: 29 December 2011.
Scandinavian Actuarial Journal
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Submitted on: 31 January 2019.
Revised on: 21 February 2019.
Accepted on: 14 March 2019.
Scandinavian Actuarial Journal
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