Hm. Why is this "theoretically"? I live in Finland and wouldn't mind requesting this data. It couldn't be more than a few days' crunching numbers to figure this out.
“Theoretically” only in the sense that most people won’t do it (since the data isn’t easily available, and you’d need to figure out who you were benchmarking against before requesting it), so the practical effect may be negligible.
What percentage of the population do you think would equally not mind submitting a formal governmental records request followed by a few days crunching numbers?