Telecommunications in China pie charts). China's number of Internet users or netizens topped 137 million by the end of 2006, an increase of 23.4% from a year before and 162 million by June 2007, making China the second largest Internet user after the United States. The latest figure (December 2011) have China's internet users exceeding 513 million making it the largest internet user in the world. As of 2004, the largest concentration of Internet users were from Guangdong, Zhejiang, Fujian, Jiangsu, Liaoning, Shandong and Hubei provinces. Beijing, Shanghai and Tianjin also had a high concentration of Internet users, with 28% of Beijing's population
Water supply and sanitation in China built in the city of Nanjing. Subsequently, China engaged in what is possibly the largest wastewater treatment investment program in history. It has been estimated that in 2006 there was sufficient capacity to treat 52% of municipal residential wastewater. According to the State Environmental Protection Agency the rate of urban wastewater treatment reached 57% in that year. The government's goal to achieve a level of 60% for treatment of municipal wastewater by 2010 was surpassed. By 2010, 77.5% of domestic waste water was treated. Between 2001 and 2004, the number of cities that charge wastewater tariffs has increased from 300