Bill Gates and his wife Melinda Gates founded the Bill and Melinda Gates Foundation, which is a charitable organization. Critics believe that the foundation was established only to respond to negative public comments on Microsoft's monopolistic behavior. The foundation has made great contributions to providing scholarships for poor students and preventing and treating AIDS, malaria and tuberculosis. On June 15, 2006, Bill Gates announced that he would retire from the daily affairs of Microsoft within two years in order to concentrate on health and education charity. On June 25th, Buffett, the second richest man in the world, announced that he would donate his assets with a market value of $37 billion to Gates Charity Fund. The Bill and Melinda Gates Foundation has about $27 billion, and with Buffett's generous donation, it has more than $60 billion. In 2006, the Bill and Melinda Gates Foundation will donate $200 million to China for AIDS prevention and treatment in China.