Social security contributions insure workers against events that may result in them being unfit for work. There is a correlation between benefits and contributions (the notion of insurance in the social security relationship), therefore certain benefits available to dependent workers in a specific sector may not be available to those in other sectors. Social security contributions therefore consist of an 'insurance premium' that is paid in to insure the worker against a specific event, such as illness, maternity leave, unemployment or a pension.
Contribution rates affect both workers and employers. However, employers are required to pay contributions for themselves and for their dependent workers.