Complex sentence: The shutdown of the Navy Yard in 1966, ended up being a result of New York's shift from an industrial economy to a more service-oriented economy, it was a sign of decline and a clear demonstration of the lost relation with the waterfront.
Split into simpler sentences: The shutdown of the Navy Yard in 1966 ended up being a result of New York's shift from an industrial economy to a more service-oriented economy. It was a sign of decline and a clear demonstration of the lost relation with the waterfront.