[Koha] How to Make report in CSV/XLS format

Hi, Is there some way that i could make a report in csv (excel) file. currently i am trying to make a report for all the students having fines in their accounts and then output it in CSV format, but the options available are just the 'coma seperated text' and 'tab seperated text'. i want a csv or xls file output. any idea? regards umer habib