AVERAGEIf across multiple sheets

Hey everyone! I use Microsoft Office 365 for this particular file and I can't figure out how to average each metric on the AGENT sheet for each individual agent for the first 13 weeks. The metrics are in row 1. The only agents I want to average are the ones that are on the AGENT sheet. I tried =AVERAGEIF('Week 1'!A:'Week 13'!A,A2,'Week 1'!B2:'Week 13'!B2) in cell B2 of the AGENT sheet, but it gives me a #NAME error.

Thanks for any help in advance!!