How do they determine which team is the home team in the super bowl?

I thought the NFL alternated between the NFC and the AFC as to which team was the “home” team each year in the Super Bowl. But, after looking at some of the recent Super Bowls, this is not the case. The NFC has worn “home” uni’s for the past 3 Super Bowls.

15LB Used Roto Grip Mutant Cell
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