I am dutch: Mortgage interest is deductible on youre income in the Netherlands. So this is why housing prices and mortgages are so sky high over here.
I have an equal amount of money on the bank as i have on mortgage debt but i wont pay it back because of the fiscal situation. If i pay back my loan my house will be seen as assets for the IRS.
I have then too pay net income on property taxes where now my interest on debt can be deducted from my income. Its a world flipped over were debt is wanted by the government.
In the Netherlands you should look at net debt instead of looking purely at graphs.