How to sum up the price of the items in the LIG only if their part number starts with something?

Summary:

Hello,

I would like to create a formula that calculates the total of items in LIG that have a part number starting with "TEN".

In order to do that I wanted to do something like that:

sumIf(startsWith(Part Number, "TEN" ),Amount (Net))

However, in the startsWith function I can only put functions, literal values , main attributes and system attributes while I need to put line attributes.4

How can I do it?

Regards,

Silvia

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