Retention settings

What settings would I use to retain all files regardless if they were deleted or not for a 3 yr (for example) period?

occasionally I get a request to restore something that might have gone missing or moved a year or so in the past.

[list]
[] Use a custom retention policy
[
] Check Delete Versions Older Than and set to 3 Years (Modification Date or Backup Date - you decide based on how you want to handle older files)
[] Check Always Keep the Last Version if you want to keep at least 1 version of every file beyond the 3 years - if not, leave unchecked
[
] Uncheck Keep Number of Versions
[] Uncheck Delay Purge
[
] Uncheck Delete Files that Have Been Deleted Locally
[/list]

That should keep all versions of every file for 3 years

thank you