The Roman Numerals of the Super Bowl

This is an interesting thing about the Super Bowl. This was Super Bowl 51. And as you might know, when they name the Super Bowls and they make the official logo for each one, because each one has its own logo, they use Roman numerals. But what they did was for Super Bowl 50, they broke with that. So when you go through and look at all the logos, it's like five zero. The one before it isRoman numerals. It's like XLIX. And the one after is L.I. That must really, really annoy, you know, anal people when they look at the list of Super Bowls - just one of them is not