The 2018 Hyundai IONIQ Hybrid and IONIQ Plug-in both earned recognition in ASG’s 2018 Automotive Performance Index (API). In fact, these two IONIQ variants swept the full-size car class to win all accolades in the hyper-competitive segment for 2018.

ASG found the 2018 Hyundai IONIQ Plug-in to offer the best value and all-around performance of any model year 2018 full-size car, earning the distinguished BEST ALL-AROUND PERFORMANCE award in class. In ASG’s data-driven life-cycle assessment, the IONIQ Plug-in furthered its winnings with the smallest carbon footprint in class, earning ASG's BEST ENVIRONMENTAL PERFORMANCE award.

In ASG's economic assessment, the IONIQ Hybrid holds claim to the lowest cost of ownership when considering purchase and operating costs across the first 6.5 years of vehicle ownership (87,594 miles - the average time and vehicle miles traveled by the average new car buyer), earning ASG's BEST ECONOMIC PERFORMANCE award in class.

And finally, when assessing all 485 large cars, across classes, the IONIQ Hybrid and IONIQ Plug-in both landed a spot in the top five, earning ASG's BEST 5 ALL-AROUND PERFORMANCE honor. BEST 5 models are distinguished among an elite group of five vehicles in their respective segments (small cars and large cars) to achieve the highest combined social, environmental and economic performance ratings.

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The Automotive Performance Index (API) applies statistical methods to demonstrate each vehicle rating in relative comparison. For example, the vehicle that performs highest in environment performance in a given class obtains a rating score of 100. Each vehicle in its class is then compared relative to the top-performing vehicle with a rating score reflecting the statistical difference in performance outcomes. A score of 91 translates to a 9% environmental performance deficit as compared to the top-performing vehicle.  

Due to the API’s relative vehicle rating method, vehicle class divisions were identified as a critical input - these class divisions are detailed here.

While the Automotive Performance Index is indeed an exhaustive list of vehicles to trim level detail, with each vehicle assessment reporting over 200 unique data outputs (the culmination of thousands of data inputs), ASG has taken additional measures to ease the burden of sorting through all data points and all vehicle assessments. We have developed key performance categories and sorted all vehicles in each class according to Environmental Performance, Social Performance, Economic Performance and All-Around Performance. The vehicle in each class with the best score in each unique category is named the performance award winner (i.e. Best Environmental Performance Award winner). The vehicle in each class that scores highest combined scores in Environmental Performance, Social Performance and Economic Performance is named the ASG Best All-Around Performance Award winner.

One step further, we also name the Best 5 All-Around Performance Award winners in each class to provide consumers with a concise product comparison guide.