However, the constitutionally protected freedom of association and collective bargaining autonomy (links to the text Collective bargaining autonomy) includes not only the right to join a collective bargaining party - but also the right to stay out of such a coalition. For this reason, the AVE of collective agreements plays a special role in the German collective bargaining system. Not every sector and collective bargaining party is eligible for the AVE of collective agreements. The comparatively low number of collective agreements declared generally binding in relation to all applicable collective agreements documents their exceptional character (443 AVE in 2017, Federal Ministry of Labour 2017).