Naming conventions of email in email performance report
Email reports will use an email's full label including the program it exists in. Although asset names cannot duplicate within Programs, they can be duplicated within the whole Instance and Email Performance Reports have access to emails from an entire instance.
For example if you had two newsletter programs, both with an email named "October Newsletter" the full program name can help differentiate between the two.
NL-2018-10-Technology Program.October Newsletter
NL-2018-10-Industry Program.October Newsletter
The email report will always display with the full email name including the program it was created in to avoid this confusion. Even within a specific Program Report, you can access all emails within the Instance.