Believe it or not, your credit score can affect your auto insurance rates. What’s a credit score? It’s a risk rating calculated from credit reports using special mathematical formulas. Lower scores result from paying bills late, having few or no credit references, or poor credit-card practices. Even fiscally responsible consumers suffer premium increases of more than 100 percent when insurers credit-score them. For 34 years, Mattie Grainger from South Carolina insured her autos with Allstate. She had a perfect driving record, few insurance claims, and enjoyed safe-driver discounts. Yet Allstate raised her premiums, telling her she didn’t qualify for a lower rate because of a low credit score. Grainger’s credit score was low because she simply didn’t need extensive credit. Many argue that applying credit-scoring in preparing insurance quotes or policy premiums is inherently unfair. We do, too.