Firstly, there is no "UN graph". The graph was created by an anonymous internet user.
The data comes from the United Nations Office on Drugs and Crime. It comes with this crucial caveat:
So there's no "UN graph". But there is a UN diagram that suggests things are more complex than they seem:
Respectfully, saying the "UN graph says it all" does not appear to be exercising the "caution" that the source of the data advises.
Exercising "caution" might be to recognise that in Sweden, crimes are recorded differently.
But don't just take his word for it. What about the UNODC? They are after all the source of the data.
UNODC research provides important context for understanding sexual violence statistics around the world.
Why is sexual violence in Sweden so high? Why is India so low? What's the difference between Sweden and the United States of America?
The UNODC tells us it's not enough for rape laws to exist. We must also consider how well they're enforced.
On that point, here is a graph the UNODC did produce. They did not produce then graph you attribute to them.