* New vs. Used: The average price of a new car will be significantly higher than a used car.
* Type of car: Luxury cars, trucks, SUVs, and sports cars will all have vastly different average prices than economy cars.
* Data source: Different organizations use different methodologies to calculate average prices, leading to variations in the results.
To get a meaningful answer, you would need to specify which of these factors you're interested in (e.g., average price of a new mid-size sedan in 2003). Even then, finding precise figures from 2003 can be challenging. You might find some information in archived automotive industry publications or through research from organizations that track car pricing.