How to calculate days between 2 dates excluding public holidays over SAP ?

Hi

Have a universe over SAP data. Trying to calculate days between 2 dates. SAP holds Public Holiday data in various tables e.g Thol and data is updated via scal. Using my univeres as a source I want to run reports for different countries so need to have various bank holidays not just UK. In SAP function modules handle this. Has anyone designed a solution to cater for this situation in a universe ?

Thanks in advance

M