This kind of flow chart is hard to get right, but I think that Torre's thoughtful decision of combining colors and subtle looping animations succeeds at making the graphic clear and enjoyable on a computer or tablet screen —mobile is a different story; you need to zoom in to see what's going on or select countries, and the hover function isn't available.
To overcome this last challenge I wonder whether it'd be good to add a complementary table showing, say, the top 3-5 destinations and the 3-5 origins of migrants when selecting a country. Something like the graphic below (the table would be displayed underneath the map on the mobile version).
(Update: Anita Graser suggests that total counts may not be the entire story. I agree; adding relative values —migration rates per 1,000 people or %— to the table is worth considering. They can be seen already in each country's tooltip.)
(Update: Anita Graser suggests that total counts may not be the entire story. I agree; adding relative values —migration rates per 1,000 people or %— to the table is worth considering. They can be seen already in each country's tooltip.)
