I debated Art Laffer yesterday in Austin–a great guy, despite being all wet on immigration. But I got to thinking before my presentation about the illustrative value of his Laffer Curve, and decided to try my hand at creating an immigration equivalent:

To interpret, modern conditions mean that the inflection point, where more immigration starts yielding diminishing returns (in a broad sense, not just economic), comes a lot sooner, and the benefits are replaced very quickly by costs (again, in a broad sense) as immigration increases.

And I got Laffer to sign the napkin I drew this on!