This might be a relationship used to refer to related records dated from today's date to 365 days ago, a scripted find pulling up a found set of records in that date range or even data accessed via ExecuteSQL.
For a scripted find, you can use this script:
Enter Find Mode 
Set Field [YourTable::dateField ; ">" & Get ( CurrentDate ) - 365 ]
Set Error Capture [on]
Perform Find 
This is patterned after the many different scripted find examples found here: Scripted Find Examples