Table EDI40 size grown too big

Hi Experts,

In our BW system; we are trying to clear some used DB space. While searching for the top 10 tables in the system. It was found that table EDI40 is consuming too much space and is on second place.
As there is no IDOC deletion job is running tin the system. There are IDOCs lying since 2006. I tried deleting very old IDOCs from WE11 and half of the IDOCs in the table got deleted. But it did not make any difference is size consumed by table. When I checked in DB02old; the size of table remained the same.

Could you please advise how can I reduce the size consumed by this table. We do not need archiving of very old IDOCs. And direct deletion and space clearance is required. Could you please advise how it can be done.

Regards

Varun