Limiting Archive Size / Date

I have Acronis 11 ( build 8, 053)
My backups have been accumulating since 2008
My backup archives are 35 GB of information.
I would like to set my backups to only maintain info for 6 months to 1 year... I doubt I would be able to just delete old archives without corrupting the backup.
I would like to know if it is possible to set date or archive size with this version of Acronis.
I have been googling where some people wrote you can set in advanced settings.. but i do not see this setting .. only splitting files into set given size.. but not limiting the size.
Please let me know thanks ...