Multiple exchange rate - AUD to USD

Multiple exchange rate - AUD to USD

Hi everyone, 

All our products are sourced from China and we either pay in USD or CNY. This is converted from AUD.

For these PO's, we are issued an invoice with 30% deposit and balance paid when goods have been shipped. This can mean a massive difference in exchange rate from when the deposit is paid to when the balance is paid. 

For example, deposit exchange rate is $1USD - $1.40AUD and the balance will be $1USD - $1.54AUD

Anyone know how I can tackle this in Zoho books as i can only allocate 1 exchange rate.


Thanks