Complex sentence: The Art League's architectural expansion began in 1989 with the Riverfront Performance Terrace; by 1994 they had raised $7.6 million, completing the new building in 1996.
Split into simpler sentences: The Art League's architectural expansion began in 1989 with the Riverfront Performance Terrace. By 1994 they had raised $7.6 million in their capital campaign and completed the new building in 1996.