I'm not sure about the numbers: this paper shows tax evasion ~15% of GDP for Greece - but that includes effectively non-taxable and not reported as GDP, black market economy revenue and thus a figure larger than the figure the Economist is quoting... I can't believe that any northern EU country has anything similar. I should repeat here (I've mentioned it in a comment before) that the M&F paper shows that personal income tax evasion is disproportionately due to the highest income decile in Greece. At the same time corporate tax rates on profits fell between 2000 and 2010 from 40% to 20% , as mentioned here - and that applies to undistributed profits, distributes profit rates' are at 40%, but the net effective rates were (in 2004 at least that I found data) among the lowest in Europe. In fact Greece overtaxes labor and undertaxes profits compared to EU averages even now.

Total revenues in Greece have been less than 40% GDP (but less than that as I mentioned here) an approximately 5% lower number than the Eurozone average that jibes with the 15 billion Euro evasion the Economist article mentions, and I suppose that Greece is on a par with other EU countries in (legal) tax avoidance?

Shipping offers around 7% GDP (here in Greek) and tourism another 15%... Tourism I wouldn't think has a much higher rate of tax avoidance than other industries. Shipping companies and tycoons are almost religiously tax-exempt, not even the income they make from shipping activities is taxed (this again is in Greek, and accurate AFAICT. It lists more than 55 special provisions in the tax code for shipping companies and their shareholders/owners. Quite shocking)

The road of excess leads to the palace of wisdom - William Blake