You don't have to manually declare your profits and losses in the tax statement because ISK is flat-taxed. Instead, your capital base for taxation will be pre-printed in your tax statement. The tax for ISK 2024 is 1,086% of your account value.
RoboMarkets annually reports to the Swedish Tax Agency on the capital base for ISK. In the tax statement, the capital base is then included as a capital income from which you can make interest deductions, etc.