UNCTAD also tracks container freight rates. Freight rates are expressed as the total price in U.S. dollars for a shipper to transport one TEU worth of cargo along a given route. Data is given for the three main container liner routes: U.S.-Asia, U.S.-Europe, and Europe-Asia. Prices are typically different between the two legs of a voyage, for example the Asia-U.S. rates have been significantly higher than the return U.S.-Asia rates in recent years. Generally, from the fourth quarter of 2008 through the third quarter of 2009, both the volume of container cargo and freight rates have dropped sharply. In 2009, the freight rates on the U.S.–Europe route were sturdiest, while the Asia-U.S. route fell the most.