Employers with 50 or more employees are not given fixed rates, but will request a quote from various insurance carriers through an insurance agent or broker. These rates can vary considerably and are based on the overall risk factors of the case. Carriers are permitted to review these groups and increase or decrease the rates based on the claims paid to the group and the premiums that the group pays to the carrier. These reviews are generally conducted quarterly, and the carriers will issue letters to the policyholders and their insurance brokers indicating the proposed changes in rate.