Note that it's not Toyota's test. It's a test cycle established by the EPA, used to test all cars against it for an apples to apples comparison. If you know what your real-world fuel economy is in the car that you are/were currently driving, calculate the % difference from the EPA numbers on it, and then apply the same % difference to the Prius' numbers and then you'll have your "real world" numbers. "Real world" numbers are whatever you individually would get, depending on how you drive and where you live and how you maintain your car. The EPA even states that "Your MPG will vary." (
http://www.fueleconomy.gov/feg/why_differ.shtml )
US EPA Fuel Economy ratings for cars going back to 1985 are available at:
http://www.fueleconomy.gov/
The cars are not put on a closed test course, but they are put on a stationary dynometer (rollers under the wheels) in a lab and "driven" in a specified pattern.
http://www.fueleconomy.gov/feg/how_tested.shtml
http://www.fueleconomy.gov/feg/fe_test_schedules.shtml
<quote>
City: Represents urban driving, in which a vehicle is started with the engine cold and driven in stop-and-go rush hour traffic. The driving cycle for the test includes idling, and the vehicle averages about 20 mph.
Highway: Represents a mixture of rural and Interstate highway driving with a warmed-up engine, typical of longer trips in free-flowing traffic. Average test speed is about 48 mph and includes no intermediate stops or idling.
</quote>
For some information published from Toyota on the issue:
Tips for better Prius Gas mileage (near end of Spring 2004 newsletter):
http://www.toyota.com/html/hybridsynerg ... ng2004.pdf
Prius Fuel Economy: Explaining the EPA Ratings
Toyota explains what the EPA ratings actually mean, and lists ways to
improve your MPG
http://autos.groups.yahoo.com/group/toy ... sage/71431
http://autos.groups.yahoo.com/group/Pri ... ssage/2742
http://www.priusonline.com/viewtopic.php?t=1079
Prius Fuel Economy Factsheet:
http://www.toyota.com/images/vehicles/p ... conomy.pdf
Can I expect to get over 50MPG in the new Prius?
(see question #6):
http://www.toyota.com/vehicles/2005/prius/faq.html
http://www.toyota.com/vehicles/2006/prius/faq.html
Other sources:
More MPG tips are in the Prius User's Guide:
http://john1701a.com/prius/prius-userguide.htm
Gas Mileage Tips from the EPA:
http://www.fueleconomy.gov/feg/drive.shtml
There are also more MPG tips in your Owner's Manual.
There is a Prius MPG calculator for the Classic Prius in the toyota-prius yahoogroup's FAQs, but I don't think anyone has recalibrated it for the 2004-? Prius yet, but it should give you some ideas where you might be losing your fuel economy:
http://groups.yahoo.com/group/toyota-prius/message/6299
In case you can't tell from the above, things like how long (or short!) your trips are, speed, tire pressures, your driving style, terrain, outside temperatures, cabin climate settings, gasoline type used, oil type and fill level, will all contribute to your final fuel economy figures.
meanwhile, on the topic of published EPA ratings, I suggest reading the following article (with plenty of citations for source data):
http://www.bluewaternetwork.org/reports ... ehood2.pdf
"FUEL ECONOMY FALSEHOODS: How government misrepresentation of fuel economy hinders efforts to reduce global warming and US dependence on foreign oil" by the Bluewater Network, 2002