TRW and two other companies, Equifax Inc. and Trans Union Corp., dominate the field of credit reporting. The other companies declined to follow TRW's lead in making free reports available, but have made other conciliatory gestures in the recent past. Equifax, for instance, has set up a toll-free telephone number for consumer inquiries.

Pressure for change has been building against the credit firms for years. New York is among 14 states that have filed lawsuits against TRW, challenging the accuracy of reports, among other things. TRW made its free report offer after admitting that 1,500 people in one Vermont town could have been denied credit because of mistaken tax lien information in their TRW files. Consumers have long complained that errors by credit-rating companies ruined their credit ratings, that the companies were slow to correct these mistakes and that the material was often used - by prospective employers, junk-mailers and direct marketers - for things that had nothing to do with creditworthiness.