After years of falling sales in the eurozone, Germany's car industry returned to growth in 2014, according to a study by the consultancy firm, EY.

The study found that the German auto industry managed to increase its revenues by 9% in the countries that use the euro compared to the previous year, topping 65 billion euros in 2014. The German market was not included in the study.

"The valley of tears appears to have been crossed," EY's car expert, Peter Fuss, said.

The study included German manufacturers and suppliers with more than 50 employees.

Worldwide the German auto industry achieved sales of 385.5 billion euros, up 7% on the previous year. Germany accounted for 133 billion euros of the total.