Install On Date in Control Panel

Does anyone know if the “Install Date” in the control panel (2008 server) is the actual day that the program was installed OR if it is the date that the application install was completed? For instance, the fixlet was installed on “Date” but the server was not restarted until a later date. I am trying to troubleshoot an instance where an app was installed but the date is yesterday’s date but there no actions for this patch.

I know windows updates can sometimes mess with the install dates. Verify from the folder properties in program files that the dates match up in programs and features.