I'm not an economist or accountant. I'm a molecular physicist. As such, I do a sort of accounting as well: I do thermodynamics, which is basically the subject of how energy moves around.
The First Law of Thermodynamics states that energy can't be created or destroyed. So, if you have a box, or a planet, or a universe, the energy that goes into that system must equal the energy coming out of that system plus the energy that's accumulated within. So, you'd think the accounting is pretty easy, what goes in stays in or comes out. But is it always that simple?
And what does this all have to do with health care?