I think audio recordings is 10 years. Screen recordings are less but I can't remember what.
You are limited by how much disk space you have to keep the recordings and also by what version of SQL you have installed and the memory.
The SQL determines how many recordings you can keep.
<500K SQLExpress
500K - 2million SQL Standard
2 - 4 million SQL Standard not on the QM base server
>4 million SQL Enterprise not on the QM base server
If you get over to portal.calabrio.com and get yourself registered they have spreadsheet you can download and that will estimate how much disk space you need for recordings
Graham