A United Nations report says half of all Afghans paid a bribe to public officials last year.
The study released on February 7 says that while there has been "some tangible progress," the cost of corruption has increased 40 percent since 2009, rising to $3.9 billion.
The report by the UN Office on Drugs and Crime (UNODC) and the Afghan government's anticorruption unit says the bribes citizens paid in 2012 were "double Afghanistan's domestic revenue."
The police, judicial system, local governments, and the Education Ministry were found to have widespread corruption in their administrations.
Afghanistan has received billions of dollars in foreign aid since the 2001 U.S.-led invasion.
Western states due to pull their troops out next year have linked future financial aid to a crackdown on graft.
Based on reporting by dpa and AFP