Report Filtered to One Rep and Summarized by DSUM

[crimedog]

I have a query I run on my data tables. I filter the query by a ComboBox on a form (Rep Name)- then button on form runs report in print preview.
I only want to have one required input for filtering. So I have a report set up with January - December as Labels and a text box for each month.
In the text box I have a DSUM calculation that limits it to current Year the month (Jan-Dec) and sums the cost.

When the Labels and Text Boxes are in the Details section it looks like it trying to use multiple reps - when I put everything in the header it looks to be one record (which is what I want - a sum of all the costs by month for the selected rep)

It looks pretty - but I have to be doing something wrong - I am getting #Type errors in my summed fields

[June7]

Post the expression used in the DSum.

Or provide the db for analysis. Follow instructions at bottom of my post.

[crimedog]

=DSum([AnnualResultsMgr].[SalesRevenue],[AnnualResultsMgr],[AnnualResultsMgr].[InvoiceMo]=12 And [AnnualResultsMgr].[InvoiceYr]=(Year(Date())-1))

[AnnualResultsMgr] is a query
[SalesRevenue] is a field in the query
[InvoiceMo] is a field in the query
[InvoiceYr] is a field in the query

The query is filtered by manager

[June7]

Need static parts of the arguments in quote marks. Not seeing reference to custom variables or form controls.

=DSum("[SalesRevenue]", "[AnnualResultsMgr]", "[InvoiceMo]=12 And [InvoiceYr]=Year(Date())-1")

Access Help has more guidance on using domain aggregates.