List(OEE_yearly::OEE%) and OEE_yearly::User = $$Currentuser
Is a Boolean expression if the expression to the left is not empty and the value in the User field matches the value of the Variable, it returns True which in FileMaker is returned as a 1. (1 = True, 0 = False)
What is your relationship between your two tables? If you have a field for the current user included as a match field in your relationship so that the relationship matches to only records for the current user, the List function alone as you have tried should return a list of values only for the current user.
If using FileMaker 12 or newer, you also have the option of replacing List with ExecuteSQL and then you can specify the User as part of the SQL query you'd set up as a parameter of that function.