COPENHAGEN - Shipping freight rates for transporting containers on the world’s busiest route have dropped by more than 20 percent for the second consecutive week and are now at their lowest level since July 24. Spot rates fell 22.4 percent to $456 from ports in Asia to Northern Europe after a fall of 22.9 percent last week, one source with access to data from the Shanghai Containerized Freight Index told Reuters. Container freight rates have so far increased in 8 weeks this year but fallen in 28 weeks. In the week to Friday, container freight rates plunged 26.9 percent from Asia to ports in the Mediterranean, fell 5.6 percent to ports on the U.S. West Coast and were down 9.1 percent to ports on the U.S. East Coast. Average rates for 2015 are $659 per TEU compared with $1,171 last year. Maersk Line, the global market leader with more than 600 container vessels and part of Danish oil and shipping group A.P. Moller-Maersk, controls around one fifth of all transported containers from Asia to Europe.