You can go even further on that European percentage and state that the typical African American is going to be heavily Northwestern European and have English, Irish, Norwegian, Swedish, German and French admixture. You see that because those are the groups that were isolated with African Americans for hundreds of years in small areas. Whenever you see a high Spanish/Portuguese or Native American admixture that right away lets you know that is a Hispanic admixture and the roots would be from the Caribbean, Central or South America. That puts to rest those ridiculous stories that people grandma's told them about being Indian.
The admixture reports of 23andme are also excellent indicators of historical events, because it shows gene flow time periods. They show what nationalities were pushed out of lands. What new ethnic groups were brought into lands and time periods in which it happened. That is an excellent indicator of how long your ancestors have been somewhere. Those African American 23andme reports are incredible, because they show Senegambian and Congo/Angolan DNA being in the USA for a long time. Then Ghanaian DNA arrived. All of that mixed with European DNA. Then within the last 150 to 200 years there was a big splurge of Nigerian DNA added to the mixture. All of those time-lines coincide with wars and other activities in West African regions that produced slaves.
