We have the same system in Finland, and it also accounts for income for capital gains. It does not, however consider assets or the increase of value in assets except during years when assets are sold (when the increase in value is converted to income).
Still, a better system than fixed fines.
We don’t have the concept of cash bail and suspects and convicts do occasionally flee. It does mean their belligerence is no longer a direct threat to our society, which is something.