SUMIF problem  "#incorrect argument set"
Hello,
I am getting the "# INCORRECT ARGUMENT SET" error when using the following formula:
"=SUMIF({Treads Extruded 2019}, MAX({Week no.}) = [Current wk no.]1, {Production Qty})"
I have attached an image of the table I am working with, removed any sensitive information.
I want to add all of the production quantity up for the current week.
Thank you in advance.
Comments

What is this range looking at?
{Treads Extruded 2019}
And what is in this cell?
[Current wk no.]1

I'll let you respond to Paul, but thought I would throw in this handy error post that helps us Smartsheet Formula Designers know why certain errors are thrown:

Hi Paul,
The range is looking at the amount of tyre treads extruded on a certain date (e.g. 40 treads of a certain size). The attachment I uploaded in the original post is what this range is.
"[Current wk no.]1" cell formula is "=WEEKNUMBER(TODAY())"
Thanks

Hi Mike,
I have looked at this before, but still unable to understand what is making this error.
I have tried changing the formula but from what I know, I need those parts in the formula for it to calculate the correct thing (even though it is not).
I find it easier to write down in English first, my outcome of this formula is:
Sum of all the production quantity treads, in the current week.
Thanks

Ok. So you actually have 2 sets of criteria. Size and Date? If that is the case, then you will need to use a SUMIFS instead of a SUMIF. Something like this...
=SUMIFS({Production Qty}, {Week no.}, @cell = WEEKNUMBER(TODAY()), {Tyre Size}, @cell = XXX)
Where the XXX is replaced by the specific size or a cell reference where the specific size is already established.
If it is only the criteria of the week number, I still suggest a SUMIFS (personal preference) along the lines of
=SUMIFS({Production Qty}, {Week no.}, @cell = WEEKNUMBER(TODAY()))
There is also a way to write it to look at the actual date column and get rid of the Week no. column. Simply change your {Week no.} range to look at the date column and the criteria for that range would be
WEEKNUMBER(@cell) = WEEKNUMBER(TODAY())