Formula Order

Hello,

I'm using 2 formulas below;

{Interaction.Date_Created} in YearToDate and

{Interaction.Call_Sub_Type} = "FC539 Letter Details" and

{Employee_1.Full_Name} = "Joe Bloggs" and

isnull({Interaction.Closure_Code}) or

{Interaction.Date_Created} in YearToDate and

{Interaction.Closure_Code} in ["Returned to CC to Investigate", "Feedback Only"] and

{Employee_1.Full_Name} = "Joe Bloggs"

As you can see I'm using 'or' but when I swap the 2 formulas round the report pulls back different results. Is there any reason why the order 2 formulas are put in to the formula expert make a difference?

Many thanks,

Alex O