I have a custom date field on the invoice. I would like to count the no. Of invoices with that custom field populated based on the custom date field value selected in the Available Filter of the saved search. For example, an invoice with custom date field value of 2/5/2021 should appear only if the saved search is filtered to included that date. Is this possible?

so you can add this custom date field in the filter region and then make summary type search if you just interesting in number of such invoices. The Internal id can be the field on which you will use COUNT function.

I wasn't sure why I asked this. It sounds so simple now. Thanks!