Renter skipped on lease. Can I add Interest to the amount owed?

[Chas Chip]

Good afternoon.   A renter of a California property I own moved out before lease was ended.  I've calculated the unpaid rent and the substantial property damage renter did.  My lease says I can add attorney fees, can I also add interest to the unpaid amount owed?   I skip traced renter and know where he lives and works now and have contact info. Thanks for any comments.