A study commissioned by Illinois Secretary of State Alexi Giannoulias has found that car insurance premium inequities are driven by factors such as age, credit, and ZIP codes. The study found that drivers with poor credit can pay more than 2.7 times higher premiums than someone with excellent credit. Older adults can also face significantly higher rates despite a safe driving record. This study supports Giannulias' push for a bill that would require the Illinois Department of Insurance to review auto and home insurance rate hikes over 10% and refund customers it determines were overcharged. However, car insurance companies argue that the bill would result in higher premiums. The bill is currently awaiting a Senate vote.