Earth was an Outer Rim planet notable for its biological diversity, which could be compared to other Human worlds like Corellia, Alderaan and Naboo, and its inhabitants' claims that Earth was the origin of the Human species. By a strange coincidence, 0 BBY was known as the year 2000, 1 ABY was known as 2001, and so on. While it is odd that such a thing happened, it was convenient for when Earth officially became a part of the New Republic. With the years like this, Earth's leaders would easily be able to associate the years.