Running Total Percent, Ignore Incomplete Data

[NewYears1978]

Hello all you lovely people.

I apologize in advance for this wall of text, and also for how confusing my explanation might be - lol.

I have a unique issue (or maybe it is not unique at all).
I have a "calendar" in an Excel doc, laid out like a normal calendar. Caveat is that for the days, there are two columns (one for current year and one for previous year). The day of the month corresponds to the current year. There is sales data within each day and there are calculations for YOY year stuff at the end column of the weeks.

The person requesting this wants a YOY Variance for the week total and month total for sales. This is no issue, when the week and month are complete, however when the week is not complete you get incorrect percentages (large negatives, Etc.)
This is obviously expected behavior since we're comparing last year's complete data, with this year's incomplete data.

One workaround I had is to check if that week was completely ended by looking at the last day of the month and if it was blank, just returning "Week not complete" and then doing the same for the month. This works, but it's not ideal, and it doesn't give us a running total but rather only a total when the weeks and month are complete.

I have a sample file, which shows this above method on tab one, then tab two is just normal for anyone to experiment with (without the week not complete bit).
I cannot think of any other way to do this, unless I can maybe somehow only have the variance calculation performed on the data that has a matching value (2022 and 2023, ie if there is data for 2022 but not 2023, don't include those in the calculation)

This might be too complex, but I thought it was worth a shot. In the sample, the fields in RED are the ones in question here.

Thanks in advance, I know this is a more complicated to explain question, so I appreciate any help. This has come up before in similar projects, but I have not sought out advise on it until now.

[dflak]

It is kind of an ugly formula, but it does copy / paste true:
=SUM(IF(M46>0,L46,0),IF(K46>0,J46,0),IF(I46>0,H46,0),IF(G46>0,F46,0),IF(E46>0,D46,0),IF(C46>0,B46,0),IF(N46>0,N46,0))

[NewYears1978]

Thanks, going to check this out now
It won't let me rep you again so soon, so I will swing back around when I can to do so.

Edit:
This is super complex I cannot understand what it is doing to learn. For me the 3rd cell you added is just showing #VALUE also (not sure if that was intentional)

Edit Again (lol):
I think I see what's happening, it's comparing the columns and then if one is not greater than 0 it's not used in the total. Therefore I get a running total up to that date. I think I can figure it out - it's a bit messy as you say but works. I just have to reuse the formula for 52 weeks of the year and for all the month totals, so hopefully it doesn't go haywire

Attached image showing it working for that row =D
I just added a helper column for the "modified" value that will be hidden, that way we still get accurate sales totals in the other column. Seems to work fine.

Thanks again Now I will work on the top Month totals and see if I can get a similar result.