My apology, Kam Fook. As I do not have a concrete answer for you, however, there are few readings materials which I’m learning from and they may be equally useful for you. Of which, I am reading Warren Buffett and Fairfax Holding’s letters to shareholders. Both of them offers great insights about their investment in insurance companies every year.
Here are the direct access to these letters.
Fairfax: http://www.fairfax.ca/financials/letter-to-shareholders/
Warren Buffett: http://www.berkshirehathaway.com/reports.html
