With the Prius craze that has hit America in the last 10 years, it makes you wonder: Is a Prius really a better investment? We are a little skeptical, so let’s dig into this for a moment.

We judge a car’s fuel consumption on a curious scale we call miles per gallon (MPG). For some strange reason, Americans seem to base their vehicle purchases around this mystical MPG number, which seems to promise the savings of unimaginable amounts. Yet the MPG scale comes with the disclaimer that actual mileage may vary, which it does. So why are we basing our purchases on this?

Let’s break it down and see what the surveys say. Let’s say you were to buy a new fuel-economy car such as the Prius. You might be spending less than $4/gallon for gas but you’re paying over $300/month on your car payment.

An older SUV that gets less than 20 MPG may cost you more in fuel, but significantly less when it comes to car payments. Think about it, buying a new car includes not only the price, but DMV fees, taxes, and higher insurance premiums.

What it boils down to is this: a new fuel-efficient car could save you about $150 on gas per month. Over a year that same car will save you $1,800 on fuel. But before you start figuring out what to spend your new found savings on, there are a few things to consider. A new fuel-efficient car can range from $20k-$30k depending on what you buy. That means that something like a Prius (~$25k) will take over ten years to become cost efficient, which is the average life expectancy of an engine or transmission! By the time you can start “saving money” you will most likely need to buy a new car.

Ultimately, a fuel-efficient car may save you money on fuel, but it still hurts your wallet just as much and probably more than the gas guzzler you might already own. Those who live in the “now” might be smiling because they are saving money on gas, while those who focus more on the long term will be even happier that they are saving their money when it is all said and done.