On the wake of yet another air traffic controllers’ strike, the major European airlines once again remember the cost of it. For once airlines like Air France-KLM, Lufthansa, British Airways, Easyjet and Ryanair agree that air traffic controllers’ strikes cost them much more than others, writes Le Figaro.

Airlines for Europe has commissioned a study calculating the damage caused by striking air traffic controllers. The study has shown that between 2010 and 2016 a 12 billion euro ($12.6 billion) of the GDP of European Union countries.

Travel agencies are by far the most impacted, with canceled flights, irrevocable hotel reservations, and lost restaurant bookings contribute 56% of the whole amount lost. Airlines make 6% of the whole amount estimated above. And lastly, 35% come from travelers themselves.

Even though France – where a new strike has just begun – had seen more than 25 days of air traffic controllers’ strikes between 2010 and 2016, however, it is not the only country that had suffered. In the same time period Greece, Italy and Portugal have experienced from 10 to 25 strike days. Overall, there were 217 ATC strike days across Europe between 2010 and 2016.

“We would want to have a link of proportionality between the number of strikers and the impact on the traffic, which is not the case at the moment,” highlights Laurent Timsit, the head of strategy and international affairs for Air France-KLM.