Japan is Vietnam's single biggest donor country. In 2007, it pledged $US890 million in aid for the country, a 6.5 percent increase from the 2006 level of $US835.6 million. Vietnam and Japan have opened a centre for research into rare earth minerals to challenge China's monopoly of supply. The elements are crucial for many modern technologies, including computers, TVs and wind turbines. In 2010 Japan and Vietnam signed an agreement to co-operate in the exploitation of the minerals. Vietnam is reckoned to be in the top ten in the world in terms of rare earth reserves. Now the two have opened a jointly financed technology centre to help to process and separate the ore with the rare elements then shipped to Japan.