[jmh530]

"The economic output of an entire nation can be useful for such comparisons when you're attempting to relate to very large financial figures."

I repeat: It's comparing a stock and a flow. You cannot compare a stock and a flow because they are different units. 103bn per year vs. 103bn as a volume of wealth. You could compare 103bn to the wealth of a country. Or you could say that it is equal to N empire state buildings, or a number of dollars that goes around the world X times. But if you compare it to GDP, then you're not comparing apples to apples.