In 2018, 17 of the 36 OECD countries had some form of mandatory or quasi-mandatory funded and private pension system in place, ensuring a high coverage of the working-age population. In Finland and Switzerland, occupational pensions are mandatory and cover more than 70% of the working-age population: employers must operate a scheme and contribution rates are set by the government. Other occupational pension systems can be classified as quasi-mandatory: through industry-wide or nation-wide collective bargaining agreements, employers establish schemes that employees must join. As not all sectors may be covered by such agreements, these systems are not classified as mandatory (e.g. Denmark, the Netherlands, and Sweden). In these countries, the coverage is close to the one in countries with mandatory systems. By contrast, in Turkey, participation in a plan is mandatory only for certain employees (e.g. OYAK for military personnel in Turkey), accounting for the relatively low proportion of people in a mandatory plan.