While I had created this topic I have mentioned I have tried to find out but could not find out calculation system. So, I do not need to know how to search as I already know. I need to know how to calculate. If you know then you can reply. If you don't know then no problem.
Note: once again I have searched multiple time and read multiple threads before posting the thread.
Oh, I'm terribly sorry. What I said is just a sarcasm. Sorry if it offended you buddy but that's not really my intention. Well, you've got enough replies that helped you out find how the Trust calculation works. mdayonliner provided links for some discussions about the topic you were seeking and pugman here provided some additional information. I won't make any further reply for now as you're question is already answered.
Please lock the thread now. Thanks and sorry again.