I am trying to figure out how to set up a function that will allow me to be
able to do the following:

I'm trying to set up a chart in Excel "4 Columns" by "13 Rows". I will be
recording an actual Weight in each one on every Monday of the year. What I
would like for the function to calculate is as follows:

Take the Weight for the First Monday and subtract it from the Goal Weight
(Located in another Cell) and report the final value (amount of weight left
to reach goal) in the outcome cell. I would like for this to progress from
block to block within the group of cells with the outcome cell showing the
latest recorded weight each time.

Examples:

1st Monday 197 Subtract Goal Weight Cell 180 = Outcome Cell 17
2nd Monday 195 Subtract Goal Weight Cell 180 = Outcome Cell 15
3rd Monday 196 Subtract Goal Weight Cell 180 = Outcome Cell 16

Thanks in advance for reading my post and any help I receive.