The result is the interactive line chart shown below. You can use the interactive version of the visualization if you have a modern, standards-compliant browser (Firefox, Chrome, Opera, Safari, etc.) or you can try Chrome Frame (Internet Explorer).
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| Resale value (%) for several popular models of Australian car. |
Interaction
The chart plots a line for each of several popular models of car. The lines can be made to represent several different values:
- Sticker price: price when new
- Resale value: price when selling the car on the private market
- Resale value (%): the resale value as a percentage of the sticker price
Data
Obtaining the data was laborious. I first determined popular makes by looking at the numbers of cars for sale at carsales.com.au. I focussed on sedans, ignoring SUVs, vans, utes etc. For each popular make I selected a couple of popular models - small and large.
Then I visited RedBook.com.au to research price history but encountered a couple of hurdles. Firstly, it isn't possible to get 10 years of price data for an individual model because RedBook only publishes the sticker price and current resale values (not the resale value last year, the year before and so on). To overcome this I used the sticker price and current resale value for comparable entry-level models from 2001 - 2011.
The second problem was that for some makes (BMW, Kia, Mercedes and Nissan) it wasn't possible to find two models that had been sold in Australia every year for the last 10 years. And no single model of Hyundai (a very popular make) has been sold continuously for the last decade.
Insights
Once I had the data I was able to visualize it, and there were a couple of surprises. Firstly, sticker price has remained fairly stable across all makes and models. I expected this would have decreased more recently, especially for imported cars, with the appreciation in the value of the Australian dollar.
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| New car prices have remained fairly stable for the past decade in spite of the appreciation in value of the Australian dollar. |
Resale values drop precipitously in the first few years of a car's life - no surprises there.
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| Resale values drop significantly in the first few years. |
What did surprise me was that when resale value is expressed as a percentage of sticker price, small Japanese cars faired best. I had expected the European marques - Audi, BMW, Mercedes and Volkswagen - to top this ranking, or even popular family sedans but it's the compact Japanese Mazda 3, Toyota Corolla, Subaru Impreza, Honda Civic and the Holden Barina (Japanese import) that top the list. The smallish VW Golf also holds its value well as does the Merc.
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| Compact Japanese cars hold their value best over the 10 years considered. |
Commodore vs. Falcon
In Australia there is a long-running rivalry between the Holden Commodore and Ford Falcon. Below are the charts comparing the two cars. Falcon and Commodore track each other closely for sticker price. However, the resale value of Falcon falls away from that of the Commodore in the first few years
although after 10 years the two are close together again. As a percentage of sticker price the Falcon's resale price is one of the lowest of the models compared, especially during its mid-life, but the Commodore doesn't fair much better.
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| The sticker price of Commodores and Falcons track each other closely. |
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| The resale value of the Falcon drops below that of the Commodore but after 10 years they're similar. |
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| The resale value of the Falcon as a percentage of sticker price is one of the lowest of the models considered. The Commodore doesn't fair much better. |
This visualization was created with D3.js, is shared using a Creative Commons license, and the source-code is available on GitHub.
