The answer to this question on the racial demographics of the world centers around the definition of “white” and “caucasian”. White being of white European ancestry, and “caucasian” being a scientific definition not focussed on skin type, and more based on craniometry (oooh, that old science).
So Egyptians are really 80% Caucasian, other North African 95%, Arabs 90%, Syria & Turkey 100%, Iraq, Iran 99%; Pakistan 90%, India 75%, Bangladesh 60%, and even Myrammar 30%. Even in subsaharan Africa, you have Ethiopia 50%, Somalia 60%, Kenya 30%. It is the Nigeria, Ghana, and Cameroon that are 0%. Going to the America’s, Mexico 80%, Columbia 85%, Equador 75%. Khazakstan probably 60%. Even in the Phillipines, there is substantial Caucasian ancestry, probably 25%, due mostly to Spanish influence, and some American.
As time goes on less and less people are pure “White”, but more and more people have substantial Caucasian ancestry. A lot of the regions of the world that are exploding in population have substantial Caucasian ancestry, including North Africa, Ethiopia, Somalia, the entire Middle East and central Asia, Pakistan, and india. I would guess that 50% to 60% of the people in the world have substantial Caucasian ancestry.
More importantly, as people migrate and races merge, off-white Caucasian is the middle race genetically, between all of them. The racial extremes of the world are China, Nigeria, and NW Europe. So the average person, genetically is the “off-white” person in Latin America, the Middle East, or India.
Now if you cross a Chinese with a Hindu from India, you get something very close to Caucasian, but of course not a white European.
So what will happen in the future, 1000 years from now, is that 90% of the world population will be on average 75% Caucasian. The Caucasian race isn’t going anywhere, it’s the median, it’s the genetic average of all the others. There will probably be no pure white people left in Europe or North America, and less and less racially pure people in sub-saharan Africa and East Asia