Evolution of American cars 1990-2020

I analyzed how American cars evolved over past 30 years. For example average engine size rose from 3.33 L in 1990 to 4.09 L in 2007 then dropped to 3.42 L in 2020 due to introduction of turbochargers that allowed downsizing engines, meantime horsepower rose from 142 HP in 1990 to 299 HP in 2020. In 2019 domestic cars averaged 333 HP vs imported cars 282 HP.

Year Make Model Trim Specs changed car names

While analyzing data scraped from Edmunds, I decided to do several changes, correcting few obvious mistakes (example: AMG models and Yukon Denali) and improving model hierarchy to reduce number of so-called models with short production period, which are actually trims of a long-production model: