Submitted on: 12 December 1998.
Revised on: 17 March 1999.
Accepted on: 16 April 1999.
___________________Astin Bulletin-The Journal of the International Actuarial Association
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Submitted on: 24 June 2009.
Revised on: 08 October 2009.
Accepted on: 08 November 2009.
___________________Astin Bulletin-The Journal of the International Actuarial Association
Submitted on: 27 September 2013.
Revised on: 01 January 2014.
Accepted on: 29 January 2014.
___________________Astin Bulletin-The Journal of the International Actuarial Association
Submitted on: 15 November 2011.
Revised on: 31 December 2011.
Accepted on: 11 February 2012.
___________________Astin Bulletin-The Journal of the International Actuarial Association