The number of older diesel cars and light vans on the road fell by 18% in 2016, national statistics office CBS reported on Tuesday.

The decline was sharpest in Rotterdam and Utrecht which have designated environmental zones banning cars built before 2001.

Several cities have introduced measures to ban older diesel cars from their city centres. These include regulations encouraging motorists to scrap their cars in 2014 and the creation of environmental zones in Utrecht that year and in Rotterdam in 2015.

There were 155,000 diesel cars and light vans registered in the Netherlands at the beginning of 2017, 34,000 fewer than a year earlier. This represents a sharp 74% decline (415,000 cars) since January 2010 when 570,000 diesel vehicles were registered in the country.

Drivers in Rotterdam have been eligible for a subsidy for scrapping their diesel cars since 2014, a regulation which expires in December this year. An environmental zone banning diesel cars dating from 2010 or earlier has been in place since 2016. As a result the number of diesel cars in the port city has halved to 2,000, while the number is a whopping 86% down on that of 2010, the CBS said.

Utrecht introduced a zone excluding diesel cars built before 2010 at the beginning of 2015 and provided a subsidy for scrapping these vehicles between the end of 2013 and the beginning of 2016. In this period the number of diesel cars registered in the city declined by an average annual 32%. With 1,500 diesel cars on 1 January 2017, Utrecht had the lowest number in the four largest Dutch cities.

Even though Amsterdam and The Hague have no environmental zones, the number of diesel cars was 24% and 20% lower respectively on 1 January compared to the year before. Amsterdam now has 5,500 diesel cars, the largest number of all cities in the Netherlands.