I've found and download history of EONIA on Bloomberg and created an Excel file for dtb as joined.
The OISEONIA is capitalised index as I need to compare with the fund Insticash.
The chart show the performance from end of N-2until now (not the perf year by year) and can be more efficient. But it's enough for me at the moment.
Other information included on the file like Money market interest rates and Stock market index are from the European Central Bank.
If someone found a better way to have the OISEONIA direct from the web, I'm intersted...