Just 15% of the Dutch workforce are members of a trade union, down three percentage points on five years ago, according to national statistics agency CBS and research institute TNO.

The biggest decline is among the over 55s. Five years ago, 31% of older workers were a union member, but this has now gone down to 25%.

There are, however, major differences between the sectors. Some 27% of civil servants and 25% of teachers, for example, are union members but membership is minimal among hospitality industry workers and farm workers – sectors with a long tradition of casual or temporary work.

In total, 1.4 million people are still members of a trade union, down from 1.9 million 20 years ago.

The Netherlands has three main trade union groupings, the FNV, CNV and the MHP.