Share contributions are transferred to the credit union on the basis of membership for the whole stay of a shareholder as member of the credit union and are the basis of membership. Over 30% of the assets of credit unions are investments in government securities, certificates of deposit of banks and savings loan associations, as well as in the parent credit unions, and other risk-free investments. Historically, credit unions have grown from the experience of credit cooperatives, but they took the experience of organizations of mutual aid of citizens by moving methods of social self-protection from labor and toward consumption. In some cases, the initiators of credit unions can be trade unions, associations such as social support centers and others. A potential new member of a credit union must submit a recommendation of shareholders in which the referee becomes a warrant of a future member of the credit union.