Are We In a Bubble?

I notice that the annual returns of the last 15 years the returns were less than 10% a year, to a total of 300% at the end.

Yet the average return of the S&P the last 100 years has been well over 10%. So wouldnt it make sense it was up 300% in 15 years, from 150 to 450? It seems very reasonable when compared to the historic average.

So is there a bubble?