About the tax evasion question again, though, the per capita in Greece is higher than the USA's. As Talos said, it's lower than the eurozone. But, tax evasion is only a measure of the money that should have been paid but wasn't. If your tax rates are lower, you could have a low tax revenue per capita AND a very low rate of tax evasion at the same time.

So, I would tend to look at tax revenue per capita, as the important thing.