I really tried to think through this and search before asking. I hate having to ask questions.
On this webpage, on the Swedish IRS' website.
It says:
Om du säljer en privatbostadsrätt med vinst ska 22/30 av vinsten beskattas. En förlust får dras av med 50 procent.
This, in English, means:
If you sell a private (owned) apartment with profits, 22/30 of the profits are to be taxed. A loss can be reduced by 50 percent.
They go out of their way to avoid "percent" for the most important part. Why? I have no idea. I've never heard or seen "22/30" in any context, and it makes no sense to me.
Some other webpage in English claims that it means 73.33333333%... Source.
Why would they mix this bizarre way of typing a percentage with the actual percentage in the same paragraph, and in other places on the same webpage? There must be a reason for this.
And if they really are going to take 73.3% of the profits, that is absolutely insane and there won't be almost anything left at all. They cannot possibly mean that. Capital gains taxes are like "30 % of the profits" in Sweden, and I assumed that selling an apartment would be at least the same or less than that. 70+%? That simply cannot be right.