I’ve hear lots of people throw numbers around in that range, so it really depends exactly when you look, but I think it would be a very similar story for most major regions/periods. You can replicate it very easily to check an exact scenario, just pick a stock universe and a time period and count how many stocks it takes to make up the return.
Here’s the US market for 2010-2020 as an arbitrary example:
If you look at total capitalisation in the US it has grown by about 19tn or ~110% from 2010 to 2020
You would have got ~30% from government bonds of the same period, so where did the extra 80% (14T) return come from?
Just look at the top performers, during this time the top 25 stocks returned over 8.5 Trillion of growth! and we only need to add up about 100 stocks to get that 14T return out of around 4000 listed for the period.