Keep in mind that for Splatoon 2(and for any game here really), the numbers given are not exact figures, and are probably in the ballpark.So 50% for Mario has actually the chance to be anywhere between 45 to 55% of the numbers of Switch sold.The same holdds true for Splatoon, which would make more sense, because Im almost sure that Splatoon sold more than 2.5 millions worldwide.
My (locked) thread about how difficulty should be a decision for the developers, not the gamers.
https://gamrconnect.vgchartz.com/thread.php?id=241866&page=1