http://reply.papertrans.cn/1/30/2914/2914-31.png
http://reply.papertrans.cn/1/30/2914/2914-32.png
http://reply.papertrans.cn/1/30/2914/2914-33.png
http://reply.papertrans.cn/1/30/2914/2914-34.png
http://reply.papertrans.cn/1/30/2914/2914-35.png
Submitted on: 20 July 1999.
Revised on: 27 August 1999.
Accepted on: 08 September 1999.
___________________Astin Bulletin-The Journal of the International Actuarial Association