Dsum

[Frank Dulk]

As would make that comparison in a query

Accumulated:dsum ("Valtot" ;"table";"DateRec <=DateRec")

In that way this giving mistake.

DateRec is a field it dates.

 

[Duane Hookom]

Since you aren't giving any more information, try:
Accumulated:dsum ("Valtot" ;"table";"DateRec <=#" & DateRec & "#")

 

[Frank Dulk]

I am using that expression to create an accumulated field, but I didn't have
success, because repeated dates exist.

 

[Duane Hookom]

Add another field comparison in the where clause that compares unique field
values such as the primary key in the table.