President Trump’s most oft-repeated pledge is his promise to “Build that wall!” He has also promised that Mexico would pay for it, despite Mexican government officials scoffing at the notion. Some observers have proposed paying for it with a tax on remittances going back to Mexico from Mexican nationals living in the US (whether legally or illegally).
To get a grasp of the size of remittances going to Mexico (and other destinations), the Pew Research Center organized data from the World Bank and the result is shown in the graphic below (graphic created by howmuch.net). The numbers only reflect money being transferred via banks and wire transfer companies (like Western Union), and does not reflect money being sent through the mail or on the persons of border crossers, which the World Bank estimates could add on another 50%.
As can be seen, the sums being sent to Mexico are staggeringly large, and a tax on it could potentially raise, as President Trump might put it, a “yuuuuuuuuge” amount of money for his wall.