To collect contributions and contribution calculations.- Let the employer pays contributions annually.- Contributions, calculated on the basis of wages that must be paid to the employee of the year. Each not exceeding 240,000 bath per year.- Given the rate of contributions based on the risks of the employer's Affairs.- When consecutive 3-year contribution at the rate of 4 to calculate the losses to determine the rate of contribution based on experience and is charged in the year 5 If the employer provides employees with a safe working will receive a reduced rate of contributions. If you do not take care of safety, must be to increase the rate of contributions. To increase or reduce the surcharge from the main employer contribution rate.