Complex sentence: In 1902, the harbor was completed and the Port of Gulfport became a working seaport that now accounts for millions of dollars in annual sales and tax revenue for the state of Mississippi.
Split into simpler sentences: In 1902, the harbor was completed and the Port of Gulfport became a working seaport. The Port of Gulfport has flourished over the years and today accounts for millions of dollars in annual sales and tax revenue for the state of Mississippi.