The functional Currency for SGD for the company. We have a deal with a USD GST registered supplier. On 1 Aug 2017, we process a USD Good Receive @ 1.38 (System Rate) to convert to SGD amount. On 10 Aug 2017, we received the invoice. The system rate is 1.39 and the GST rate stated on Supplier invoice is 1.40.
Which rate should I use to recognise my inventory? If recognition of rate inventory is using 1.38, should the differences in exchange rate be charge to unrealized exchange gain/loss?