The Inc. 5000 is an annually released list that tracks the 5,000 companies in the U.S. that are experiencing the highest revenue growth. Of those companies on the 2020 list, 188 are headquartered in PA.
The literature shows that high growth firms (defined as firms experiencing 20% or greater compound annual revenue grown over 3-years) are responsible for a significantly outsized contribution to economic growth and job creation. It also suggests that small, young, and knowledge-based firms are much more likely to achieve the levels of high growth seen on this list.
The Brookings Institute conducted an analysis and general endorsement of the list: https://www.brookings.edu/research/high-growth-firms-and-cities-in-the-us-an-analysis-of-the-inc-5000/
Source: INC 5000, Introducing the 5,000 Fastest-Growing Companies in America