Central Americans crossing into US are big business. Remittances comprised over 16% of GDP of Honduras and El Salvador in 2013, Guatemala and Nicaragua approx. 10% of GDP

2013 remittances from US to Honduras, El Salvador, Guatemala, Nicaragua, and Mexico. Chart from Howard G. Buffett presentation

page 15,  "Financial incentives"

"Many immigrants send money back to family members in their home countries. These remittances play an important role in the livelihoods of the individuals who receive them and the economies of the receiving countries. 1, 2"

"1. The World Bank Remittances
2. USAID website for ODA data"

March 17, 2015, "Written Testimony Submitted by Howard G. Buffett, Chairman and CEO of the Howard G.
Buffett Foundation, to the Senate Homeland Security and Government Affairs Committee Hearing on “Securing the Southwest Border: Perspectives from Beyond the Beltway”," The Howard G. Buffett Foundation

=========

Note: Following is how I got to the above testimony:

1. "[PDF]

   Written Testimony Submitted by Howard G. Buffett, …

   www.hsgac.senate.gov/download/?id=5c7a11e5-7449-4e2a-ab72-6016af0bc1ec

   Written Testimony Submitted by Howard G. Buffett, Chairman and CEO of the Howard G. Buffett Foundation, to the Senate Homeland ... issues in the United States, ..."

===========