Automotive Lease Guide and consumer automotive advice web site Edmunds.com have launched a new rating system to tell car buyers what their potential purchase might be worth in three years.

The rating system uses one to five to stars, with one denoting vehicles in the worst 10% and five the top 10% of depreciation performers in the Automotive Lease Guide's annual RV data covering 260 models. Depreciation rates are calculated not from from list prices but the transaction prices researched by Edmunds.com.

Edmunds.com says, “Using transaction prices makes the starting values more accurate than basing them on sticker prices, especially for U.S. brands, which carry the most rebates and other incentives.” While UK consumers can refer to publications such as Parker's guides to check used car prices, new car rating systems in British automotive consumer media do not systematically advise buyers of new cars' whole-life costs as does CAP for corporate buyers. Depreciation is the biggest factor in whole life cost projections.