1)of what's been documented in during a limited stretch of the Trans Atlantic slave trade in a specific area..
2)last time it coincides with the contemporary AA population considering exotic looking lightskin blacks are a minority of the greater AA populaiton
3)your chart said 23%(a significant number) of slaves came from the Senegambia region which this source you posted in another said:
Africans from the Senegambia were considered taller and lighter complexions" A preference for light-skinned slaves preferred to work in the house.existed in Charleston, New Orleans, and some other cities."