An Insurance Research Council (IRC) study finds that the average auto-insurance expenditure in relation to median income has declined from the 1990s into the 2000s, but a consumer representative warns against confusing improvement with actual affordability.

The IRC study, "Auto Insurance Affordability," says the ratio of average auto-insurance expenditure to median income fell by more than 9.5% from the '90s to the '00s. Analyzing only the lowest-income quintile, the study says the ratio declined by 9% over that time, "implying a strong improvement in affordability from decade to decade for those in the lowest-income quintile."

Looking at the 1990s to the 2000s, all states but Alaska, Florida, Louisiana, Michigan, Montana and Wyoming showed a lower ratio in insurance expenditure to median income, according to the study. All 50 states and the District of Columbia showed a lower ratio when comparing 2001-2005 to 2006-2010.