REUTERS/Regis Duvignau
In the past decade, automakers have done an impressive job making
The 1973 oil crisis pushed automakers to focus on fuel economy, so miles per gallon numbers skyrocketed in the late 1970s and early 80s, while vehicle weight and horsepower dropped - less power, less gas used.
Over the next two decades, horsepower shot up, while fuel economy steadily dropped - more power, more gas used.
2005 marked a turning point: That's when technological innovations allowed automakers to pump up horsepower and fuel economy at the same time. Now, we have cars that weigh the same as they did in 1975, but are 80% more fuel efficient and 60% more powerful.
Those innovations include the increased use of lightweight materials, better engines, and the rise of hybrid car sales. The 2014 Ford Fusion Hybrid S gets 47 miles per gallon and produces 188 horsepower, an impressive combination. Electric cars like the Tesla Model S make up a tiny portion of vehicle sales, but also push the power and fuel economy numbers up.
Non-hybrid cars are benefiting from advancing technology, too: The 6.2-liter engine in the new Chevy Corvette gets an EPA-rated 29 miles per gallon.
Here's the chart:
EPA
And a look at how carbon emissions and fuel use have dropped since 1975:
EPA