Complex sentence: Calera's population was 3,158 at the 2000 census, but as of the 2010 census the population had more than tripled to 11,620, making it the fastest growing city in Alabama.
Split into simpler sentences: Calera's population was 3,158 at the 2000 census. As of the 2010 census the population had more than tripled to 11,620, making it the fastest-growing city in Alabama.