Summary: Investment advisors typically recommend that you put somewhere between 50% and 75% of your stock investments into US stocks and the rest into international markets. Most individual investors have 70% or more of their stock money in the US or their home country, a phenomenon that’s aptly called home country bias. But there are reasons to believe that even 50% is too much.
Disclaimer: I am not an investment advisor and this is not investment advice.
Published 2017-03-26; last updated 2026-01-24.
A note from 2026: US equities handily beat international equities from 2017 to 2025. I still believe the arguments I originally wrote are mostly correct, although I was overconfident about their strength; and there was a good justification for home country bias that I wasn’t aware of, namely, expropriation risk.
I originally wrote that US investors might want to invest only 0–30% in US stocks. I now believe that’s taking it too far. I believed that the strongest argument for under-weighting US stocks was income diversification, but the correlation between domestic equities and personal income isn’t high enough to justify a 0% weighting.
Although I was overconfident in 2017 and wrong about some things, I believe I was correct to criticize most justifications for home country bias, and I don’t believe US equities’ subsequent outperformance was predictable ex ante; see Asness, Ilmanen & Villalon’s International Diversification—Still Not Crazy after All These Years (2023).
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