51It must therefore be held that, by retaining and applying rules providing for the application of a formula for calculating the engine rating for administrative purposes which is unfavourable to vehicles fitted with a six-speed manual gearbox or five-speed automatic transmission, which has discriminatory or protectionist effects in the case of vehicles manufactured in other Member States compared with similar or competing domestic vehicles, the French Republic has failed to fulfil its obligations under the first paragraph of Article 95 of the EC Treaty.