The process of dealing with such a form is much more complex than in other countries and than it should be in itself, and the loss is not included in the final calculation if the transaction was not linked to the same share a sufficient time away. In other countries they have it so that you just write out your total profit, which your broker calculates for you, and then they just deduct a % of tax based on that. But for shares that you hold for a longer period of time and on which the tax is less, it is filled in as it is now, because there are not so many of them.