Ok, I see what you are talking about.
I used the following syntax which worked perfectly.
=Sum(IIf([casecounts]![Casenumber] Like "bp*" And Year([CaseCounts]![CaseDate])=Year(Date())-1 And [CaseCounts]![Week Number]=[Forms]![weekqry]![weekNumber],1,0))
In the ending 1,0: the "1" is the...