Estimates range from 4.8 million to 9 million: How Many Americans Live Abroad? (aaro.org)
That would range from 1.4% to 2.7% of Americans are living abroad at an instant in time. Many are overseas temporarily (study abroad, work assignments, military assignments, extended travel, and retirement) and eventually return to the U.S. Most Americans find living in another country to be difficult, in part, because of U.S. tax and banking regulations. Living abroad is not always the typically fictional Shangri-la image peddled by the media.
Is that more or less than the number you expect to be living outside the U.S.?