As per ATO's information about captial gain tax on overseas asset: "If you acquired an overseas asset before you became an Australian resident, you are taken to have acquired the asset when you became an Australian resident.". However, the shares I bought earlier has de-preciated unfortunately. I.e., on the date I became an Australia resident, the share price is lower than the original share price when I acquired them.
So when I sell the shares in future, can I take the original share price as reference when calculating the captial gain tax? Or must I use the lower price on the date becoming an Australia resident, which may result in a higher capital gain tax?