Multicurrency Exchange Rate

Hi,

Just a quick question hopefully....

I have just set up multicurrency, as I might be starting a new contract in Belgium shortly and I believe that my invoices will be billed and paid in Euros.

Now, each time I raise a bill, the euros side will be fine, as I will bill in Euros and will be paid that amount of Euros, but the conversion from my business account, I suspect will differ each time, since the exchange rate will fluctuate.

My question is, if I set the exchange rate in the settings manually, will this affect past invoices?  By that, I mean would it go back and amend the exchange rate used in all previous invoices?  Or will this only impact new invoices/payments received?

Obviously, the aim is to end up where the converted (exchanged) euro payment in to Pounds matches the Pounds amount on my invoice so that everything matches up nicely :-)

Thanks

Andrew