The U.S. State Department’s international narcotics report for 2015 says that half of remittances sent from the diaspora back home were processed by hawala dealers. Hawala is the traditional Islamic method of transferring funds. Hawala is also a preferred method of sending money among terrorist groups because of the difficulty in tracing such transfers. The remittances handled by hawala amount to $9 billion according to the report:
From January through November 2014, the Pakistani diaspora legitimately remitted approximately $18 billion back to Pakistan via the formal banking sector. Though it is illegal to change foreign currency without a license, unlicensed hawala/hundi operators are prevalent throughout Pakistan, and it is estimated that use of these operators accounts for over half of the total remittances. Unlicensed hawala/ hundi operators are also common throughout the region and are widely used to transfer and launder illicit money. Some support the financing of terrorism.
The report goes on to note that unlicensed hawala is especially common in Karachi and Peshawar.
By the way, even a 50 percent registration rate of hawala businesses is higher than it is in the U.S. Our authorities are only licensing 17 percent of hawala dealers according to a study out of George Mason University.