I know, but that's definitely the first reason OP will say as an excuse IMO and I just posted in advance before OP had a chance to say it. But since OP already have what he/she is looking for and he/she already knew how to use the search function. Maybe he/she can lock the thread now. Also, is this discussion really belongs here?
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.