Tax wedge: France = Greece = Top OECD countries

"In 2012, the highest tax wedges for one earner couples with two children at the average wage were in France (43.1%), Greece (43.0%), Belgium (41.4%) and Italy (38.3%). New Zealand had the smallest tax wedge for these families (0.6%), followed by Ireland (6.4%), Chile (7%), and Switzerland (9.5%). 

The savings realised by a one earner married couple compared to a single worker were greater than 20 per cent of labour costs in the Czech Republic and Luxembourg and greater than 15 per cent of labour costs in five other countries - Germany, Hungary, Ireland, New Zealand and Slovenia. "


http://www.oecd.org/tax/tax-policy/taxingwages.htm