ISFILTERED Returning TRUE

Hi,

Any thoughts as to why the following DAX is returning TRUE for the BillingDate Column?
I do realize there is a filter applied in the variable but that’s a different column than the date. Am I misunderstanding something? There is a relationship between Sales and Billing Date on the Billing Date column. Thanks

DEFINE
VAR _FilterDateRange =
    FILTER ( 'Billing Date', 'Billing Date'[Year] = 2019 )
EVALUATE
SUMMARIZECOLUMNS (
Site[Site Code],
_FilterDateRange,
"Tons", 'Sales'[Invoiced Tons],
"Filter", ( ISFILTERED ( 'Billing Date'[Billing Date] ) )
)

I’m a little confused with your question. I see your variable, and that you used it in the measure below. What is it that you are trying to calculate? If it is a bit tough to describe, please provide a PBIX to help us come up with a solution.

Thanks
Jarrett

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