To the best of my knowledge, that is true. If each and every year, there's a change of some sort, a sale or outflow of those assets, the difference between the fair market value and the cost value should indeed be taken into account.
A check would be necessary to determine whether it would directly affect the debt, the accumulated deficit, or whether it would be considered an expenditure. Regardless, you are right.
That's true for every year. It's also possible for some of those assets to have a higher market value than the original book value. That's generally what happens. Most of those assets go up in value.