inflow是什么意思？

Some argue that people are anxious and feel threatened by an inflow of new workers.

What is the chief concern of native high-skilled, better-educated employees about the inflow of immigrants

But over the next few decades labour forces in rich countries are set to shrink so much that inflows of immigrants would have to increase enormously to compensate: to at least twice their current size in western Europe's most youthful countries, and three times in the older ones.