That's hardly unusual. There are many, many foundations that have been endowed with a large sum that they invest. Many such foundations give away the interest they earn and aim to keep their capital roughly unchanged. Others attempt to spend their money slowly.

When I was a student I ran into a foundation that's been doing it for almost 200 years now, and I'm on the board of a foundation that's much younger but follows the same model.

Let me actually give an example. A little over a hundred years ago, someone who had earned a lot of money decided to set up a research foundation. His goal was to build a house, establish an organisation, and after that provide a steady sum each years, enough to pay the salaries of… I think his plan was 20 researchers.

His accounting would be similar to Elon's now.