When I submit a SOQL query, it appears that no records older than one year are returned. Is this indeed the designed behavior? Is there a way to retrieve records older than one year via a SOQL query?

Example:
Select from Event where OwnerId = ''

The results include all the Event records owned by the owner id specified, except that events older than one year are not in the result set.

Can anyone tell what the absolute limits are in this regard and what if any options I have to retrieve records older than one year? I couldn't find any mention of this limitation in the message boards or the API documentation.

Thanks!