Just a quick thought.
If I consider how much of my in-game wealth is in play – being actively used on the markets or flown in and around space, the total would not reach 10B ISK.
I would have a further 10B ISK of assets which I call memorabilia. Aside a handful of times when moving home station, these never interact with the game. They are collectibles and hanger ornaments that please me in different ways.
As a self-proclaimed risk-averse Carebear, I have slowly but surely accumulated wealth in excess of what I use in game. This primarily sits in a couple divisions in my Corporation wallet.
For all intents and purposes, the large majority of my wealth is effectively unused and out-of-game. I wonder how common that is – and just how big that ISK sink is amongst carebears.