How can I know the expenses of one account/currency


New Member

I have two current accounts with different currencies (EUR and NZD). I get my income only in the EUR account but I have expenses in both accounts.
How can I check the money I'm spending monthly from the NZD account so I know how much money to send from EUR to NZD?
I have also a saving account in NZD so not all the money "leaving" the NZD account is an expense (it can be a transfer to the saving account).