According to the liberal think tank Concorde, over the last 20 years France has missed out on one million new jobs because of the knock-on effects of French people going into tax exile.

Concorde bases its finding on the fact that that 3 percent of the two million French expatriates living abroad now own companies, running firms with at least ten staff on the payroll.

If these entrepreneurs had not fled L'Hexagon, as France is often referred to, then there would be now be an extra 60,000 companies employing more than 70,000 employees, the think tank concludes.

But because the flight began 20 years ago, Concorde works out a hypothesis that these "lost companies" would have employed around 35 people each. It then divides this in two because of the fact that these companies could not have been set up or developed in France.

The result: One million jobs lost as a result of tax exile.

The figures are of course only estimates based on a theory, but nevertheless, the report, published in right-leaning daily Le Figaro comes at a time when a debate over taxing high earners continues to rage in France.

After much hullabaloo, President François Hollande’s flagship 75 percent tax rate on top earners looks like it will never see the light of day. That appears to be good news for people like actor Gérard Depardieu, who was heavily critical of the proposal before he upped sticks and moved to Russia.

Stories of wealthy French nationals fleeing abroad have been a regular feature of the right-leaning press in both France and even Britain in recent months, but in reality there is little reliable data to prove that the number of tax exiles has increased since the socialist government came to power last June.

In its study, Concorde uses a series of indicators to suggest an acceleration in the number of people seeking tax exile last year, including the fact that the sale of property worth more than €1.5 million has shot up.

However, in an interview with The Local earlier this month Fabienne Petit, director of international activities at French firm Humanis, which works with French expatriates, said it was a myth that the French were leaving to go abroad for tax reasons.

Even so, politicians on France’s right are desperate to find some clear data that Hollande’s tax policies are forcing wealthy French people to seek better financial climes abroad.

President of the opposition UMP’s Finance Committee Gilles Carrez has already found out that between March 2011 and December 2012, 250 French nationals paid an exit tax upon leaving France.

However the tax is only payable by those who hold over €1.3 million worth of shares, so the stats again are inconclusive.

But Carrez wil not give up, vowing to go back the Finance Ministry to get hold of clear data.

“For constructive debate,  it is essential to measure this phenomenon,” he said.

Philippe Marini, president of the UMP’s Finance Committee in the Senate is also on a quest to unearth figures to prove that Hollande is causing the wealthy to run away from home.

He has asked the Finance Ministry for data on the number of departures abroad that are liable for income tax.

But for now, the question of tax exile looks likely to rumble on.