Yes, I can use it in a SUM statement, so I assumed the syntax is valid, but it won't let me put that same syntax in the Series Value box when specifying what data to use for my chart.

And yes, my example is intentionally meant to go across a single row. I have many single rows, each with their own chart. If I could use the statement with an OFFSET in the Series Values, I could reuse it for every chart. If I can't, the it looks like I will have to create a separate range name for each chart (18 of them), which is doable, but I'm trying to avoid it if it isn't necessary. Thanks.