echange rate from LOC/EUR to EUR I have import values in LOCEUR (LOC is local currency). 
How can I obtain these values only in EUR? My data are from Eurostat, where external trade indicator is "Exports in million of ECU/EURO"
If you mean you want to convert ECU to EURO, they are essentially the same currency; one was a basket of European currencies used before 1 Jan 1999, the other is used after. The exchange rate is exactly 1 ECU = 1 EURO (reference) So you should be able to use that as EUROs.

Note: This came from my comment above, which I take that it helped the OP. Just to boost up answered questions ratio for this site.