What percentage of the current American population are the descendants of third-generation or older immigrants of the original Thirteen Colonies before 1776?

So I was surfing online and came across this discussion:
“https://history.stackexchange.com/questions/19099/what-percentage-of-the-population-in-the-thirteen-colonies-in-1776-were-first-se”

So it got me curious about the historical demographics of the U.S. Wondering if anyone here has insights or ideas on the topic. Thanks!