Hi,
Standard data source will pulls delta records based on a field which was selected change document(similar option at data element screen.)
First you need to find on which field was enabled for delta. if your changed fields(interest % and transaction type) are not relevant delta fields then it won't pulls data.
Please recheck your field which is relevant delta one, check thru at RSA2.
Please check the below discussion. might be useful.
http://scn.sap.com/thread/3207238
Thanks