I chose 6.0% - 6.9% too.
I think fertility rates and immigration will start to pick up some throughout the decade, though (after reaching rock bottom in 2020). Biden is big on immigration as we all know.
Counterbalancing this, though, are the effects of having an entire year of population growth removed from us in the form of 2020, and also, the aging and deaths of the baby boomer generation. So it'll turn out a wash in the end, most likely, in my opinion.
The 2020 census results themselves are overall much more positive than expected for us Americans, and it's very nice how we got past 330 Million.
Imagine how we would've done had our population been 2 million smaller than expected (IRL it was 2 million bigger than expected).
This is what I'm expecting. Based on growth decreasing from 13.2% to 9.7% to 7.4%, (3.2% less population growth 2000 v. 2010 and 2.3% less 2010 v. 2020) I would guess maybe 1.5% less population growth which would result in total population growth of 5.9% in 2030. I'll be optimistic and assume some handful of factors (more immigration, improved health statistics, baby boomers living longer than previous generations, a post-Covid baby boom, etc.) will bring the total US population growth to above the 6.0% threshold.