Not an exact answer to your question, but self identified blacks are not very African http://blogs.discovermagazine.com/gnxp/2011/02/brazilians-more-european-than-not/ …pic.twitter.com/uhvkiSK6Dz
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The question can be reformulated more reasonably, e.g. if around 50% of US blacks are >80% African, how many Brazilians are that African?
Why not just ask about the averages? Brazilians are more admixed, few are that African. Mostly northeast coast.
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