Outsiders, like me, who are trying to understand how much immigration is driving the "Brexit" debate about the European Union might consider this fact: Britons are much more likely today to encounter people born in another country — both inside and outside Europe — than they were a decade ago.

In 2014, about 1 in 8 people residents were born outside the U.K. — up from about 1 in 11 a decade earlier, according to government statistics.

I posted a table yesterday showing the top countries from which those residents immigrated. India tops the list. But countries like Poland, Lithuania and Romania, where residents are now part of the E.U. and eligible to work in Britain, have seen hundreds of thousands of residents leave for the U.K. The number of Poles, for example, increased more than 700 percent.

This bar chart is another way to view that data, in raw population terms, to better understand the makeup of the foreign-born population:

This bar chart shows those immigrant countries, sorted by percentage change since 2004: