Trade carried by sea has grown fourfold since 1970 and is still growing. In 2011, the 360 commercial ports of the United States took in international goods worth $1.73 trillion, or eighty times the value of all U.S. trade in 1960.— Rose George
Trade carried by sea has grown fourfold since 1970 and is still growing. In 2011, the 360 commercial ports of the United States took in international goods worth $1.73 trillion, or eighty times the value of all U.S. trade in 1960.