For comparison, when I appears after X, as in XI, that indicates 10 + 1, which equals 11 ... Roman numerals each year.

For comparison, when I appears after X, as in XI, that indicates 10 + 1, which equals 11 ... Roman numerals each year. Therefore, the league retroactively renamed Super Bowls one through four ...

Roman numerals are a numeral system which was used in Ancient Rome. It uses letters instead of numbers to represent values. You may have seen Roman numerals on clocks and on TV or film credits.