When insert a new row, the existing formulated is appearing instead of new

Hi,
I've setting up new formula as per attached file at the column 20 onward but when i insert new row, i can see the old formula is appearing instead of new.
The existing formula was written by ex-colleague therefore, it is so hard to trouble shoot this. could you please help.
Thank you.

Im not a table expert, but I have taken a look at your upload. Clearly you are making adjustments to the table, and the whole thing does look quite complex, but I can't understand what you mean about "see(ing) the old formula instead of new". Its not clear where you are trying to insert the row thats producing the problem either, or which formula you believe to be wrong.
I tried inserting a row, and the inserted formulae were adjusted correctly where they included cell references. Any constants, named ranges or function names would of course be copied without alteration. Looking briefly at the data, I couldn't understand where the formula placed in L18 is coming from (having inserted a new row), as it was completely different from neighbouring formulae in column L.
If you can repost your example with more explanation and an illustration of where your inserting and what you believe is wrong with the formulae, I can certainly take another look, but this one looks difficult to handle without seeing the actual worksheet(s), which might mean you need professional help.

Hi Hercules 1946,
Thank you for your reply.
No worries about the formula. They all working well however, i can't understand that why the new formula unable to re-write the old formula when new row was inserted.

Example as below.
The new formula is in blue but when i tried to insert the new row normally i just click at the row number to insert a new row. I can see that the old formula is appearing refer the one highlighted in red. Do you know which excel functions allow to lock/protect the formula and also, auto repeating the formula when insert the new row? i really need excel expect to help me on this.
Thank you.

Hello Mango Koh
This kind of problem can be a bit of a nightmare for an advisor because we don't know what steps have occurred earlier to arrive at where you are now.
It sounds as though you have made similar changes before without experiencing these problems, so you might have unwittingly done something extra/differently on this occasion. I hope that you have taken the precaution of saving the worksheet in its original form, and not overwriting/deleting this until you are certain that your amended worksheet is fully functional. Most of us have tackled new territory in update projects, and the key thing is to proceed in small steps, save a number of working copies, and check thoroughly between steps. That way if you make a mistake, you can undo and try something else. If you still have the original (fully functioning) worksheet and you feel "out of your depth", you may be better getting a professional to look at it, but they would need the required amendments to be fully specified.
You could start again working along the lines Ive suggested, or simply amend the formulae that are wrong. My guess would be that you have inserted or deleted something thats upset the structure of your table. The table tools have their own facilities for inserting/deleting rows/columns (see the Cells group on the Home tab).