When private individuals have their money in savings accounts, aren't the banks investing that money anyway ?

Practically, yes. But in economics they often classify “savings” only as being in a bank account. So if you “save” money in a 401k, where it’s invested in stocks, bonds or ETFs or whatever, then it’s not recorded as savings because they consider that “investment”. So when someone says EU saving is 18.79% vs US saving of 3.50%, most of the wealth saved by Americans isn’t showing up in that comparison because it’s not in a bank account.

If it is just a matter of classification, then why would part of the problem lie on lack of private investment, when private savings are invested by the banks themselves ?

I think a big a part is that a lot of EU money is invested in the US instead, and I am looking forward for that to stop..

There’s a whole lot of regulation around the types of investment a bank can make with the money. Most of it has to be low risk mortgages, loans and high quality bonds.

Makes sense, thanks !

Isn't it a huge issue for Europe, that stock revenue is heavily taxed, while pensions accounts (which make the same investments) are not?

Which means it makes more financial sense to put the money into pensions accounts?

I’d be very surprised if that site wasn’t counting stocks as savings.