Caluculation for adding up cells if the cells are a certian colour

Hi all,

I am looking for some help, I have been stuck on this for over a day now and have given up!

I am looking for a formula or some help with a macro for creating a formula that will add up numbers that are not in a range and returning a total value.

i.e. in row 5 if yes is selected the cell will turn green ( I have managed to complete this), I then need to add up all the numbers that are contained within the green cells only and the a total value that are green returned in G5. But I still want to include the cells that are not yet green in the formula/sum just in case they do become green later on.

I have attached a sample of the workbook and I hope the above makes sense?

Many thanks for any help that can be offered.
Kind regards