The Danish and German economies have benefited most among 14 EU countries from the expansion of the bloc's single market between 1992-2012, according to a study published Monday (28 July) by the Bertelsmann Stiftung, a German foundation.

Over those 20 years, German real gross domestic product rose by an average of €37 billion per year, translating into a yearly income rise of €450 per person. Danish citizens had a yearly income rise of €500 over that same period.

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Austria and Finland rank third and fourth, respectively, with gains above €200 per person, followed by Sweden and Belgium (€180).

At the other end of the scale are Italy (€80/year/person), Spain and Greece (€70/year/person) and Portugal with an increase of only €20 in per capita income per year.

The study is based on an own-devised econometric index which quantifies the EU single market's impact on growth.

But it only took into account the 14 states belonging to the EU before the its eastward expansion in 2004. Luxembourg was not included because of "large data gaps".

The study also quantifies how these 14 economies would have fared in the absence of more EU integration since 1992.

Again, Germany and Denmark would have lost the most: over two percent of their per capita GDP in 2012 would have been scrapped if there was no EU single market. This would have led to personal income losses of €720 per year in Denmark and €680 in Germany.

According to the study, only Greece would have gained from no EU single market: its per capita GDP would have been higher by 1.3 percent or €190.

The Bertelsmann researchers also looked at the levels of integration of the states surveyed: Belgium, France and Ireland top this ranking with scores above and little below 80 points on a 0-100 scale, respectively.

At the other end is Greece with an integration score of 47.6 points in 2012, compared to 33.9 in 1992.

Germany and Denmark stand out again with the highest integration leaps over these 20 years. Germany went from a score of 49 points in 1992 to 76.3 in 2012, while Denmark jumped from 45.6 to 68.7 points.