An organization that collects statistical data (such as premiums, exposure units, and losses), computes advisory rating information, develops standard policy forms, and files information with regulators on behalf of insurance companies that purchase its services. Years ago, insurers were required by law in most states to belong to the designated rating bureau and to use its rates and policy forms. Today, however, these organizations serve in an advisory capacity for most services and most coverage lines; generally, insurers are free to use their products and services as they see fit. The best known rating bureaus are National Council on Compensation Insurance (NCCI) (for workers compensation insurance), the Surety Association of America (SAA) (for surety bonds and crime insurance), Insurance Services Office, Inc. (ISO) (for most commercial and personal lines other than workers compensation insurance), and American Association of Insurance Services, Inc. (AAIS) (for many commercial and personal lines other than workers compensation).