More and more Americans are opting to not only travel abroad but also live there permanently.

It could be the dollar exchange rate, and other financial incentives.

Now, more than 5.1 million Americans are expats and that number is growing.

And where are the most popular destinations?

Mexico is one, where so many Americans now have second homes.

Portugal has attractive special visas.

Spain offers one of the lowest costs of living in Western Europe.

Germany has more than 121,000 Americans living there. The Netherlands now has more than 31,000 Americans calling it home.

A growing number of Americans are retiring in Costa Rica, along with Panama. Many of these countries offer attractive tax incentives, and in the cases of Costa Rica and Panama, a great health care system.