It’s no surprise that the Afghan government is dependent on foreign aid to function. But it’s striking to contemplate just how dependent it has become.

According to a new analysis by the Government Accountability Office, the United States and other donors funded 90 percent of Afghanistan’s total public expenditures from 2006 to 2010. In fiscal 2010, the Kabul government’s entire domestic revenues came out to about $1.6 billion.

For comparison’s sake, since 2002, the United States has allocated over $72 billion to the mission in Afghanistan.

In a letter to Congress, the GAO notes that it has repeatedly raised concerns about Afghanistan’s ability to fund its public expenditures, a concern that is particularly salient with the drawdown of U.S. forces. Three years before foreign troops are slated to hand over all security responsibility to the Afghan government, there are growing questions about how Kabul will be able to support its army and police force, among other parts of the government.

Full report from the GAO can be found here.