My Vanguard account, which I've had since 2007, is showing 10.8% returns over the past 10 years.

I think the difference between 10 and 15 is pretty large since the recession started over 10 years ago, but under 15.

You are right, but even 15 year returns are still above 8% with VTSAX.

Exactly my point! We can’t grow at 7% in perpetuity; so at some point it’s going to have to slow down. It feels like that’s starting to happen.

Why can't we? From my point of view, we've just began. Maybe we will see a low decade now, but the decade after that will be incredible.

Also keep in mind we already had a "low" decade... the "lost decade" of 2000 through 2012-ish. That was a bad time for investing.

+1, doesn't it seem like ML can drive just as much GDP growth as the technology that spurred growth over the past decades? it's not clear the US will be at the forefront, but nobody is stopping investors from diversifying their portfolio globally.