What does the Kauffman Index of Entrepreneurship measure?

"The Kauffman Index of Entrepreneurship series is an umbrella of annual reports that measures how people and businesses contribute to America’s overall economy. What is unique about the Kauffman reports is that the indexes don’t focus on only inputs, as most small-business reporting has been done in the past; they report primarily on entrepreneurial outputs—the actual results of entrepreneurial activity, such as new companies, business density, and growth rates. The reports also include comprehensive, interactive data visualizations that enable users to slice and dice a myriad of data nationally, at the state level, and for the 40 largest metropolitan areas. The Kauffman Index series consists of three in-depth studies—Start-up Activity, Main Street Entrepreneurship, and Growth Entrepreneurship. The Kauffman Index of Startup Activity is an early indicator of new entrepreneurship in the United States. It focuses on new business creation activity and people engaging in business start-up activity, using three components: the rate of new entrepreneurs, the opportunity share of new entrepreneurs, and start-up density. The Kauffman Index of Main Street Entrepreneurship measures established small-business activity—focusing on U.S. businesses more than five years old with less than 50 employees from 1997 to 2016. Established in 2015, it takes into account three components of local, small-business activity: the rate of businesses owners in the economy, the five-year survival rate of businesses, and the established small-business density. The Kauffman Growth Entrepreneurship Index is a composite measure of entrepreneurial business growth in the United States that captures growth entrepreneurship in all industries and measures business growth from both revenue and job perspectives. Established in 2016, it includes three component measures of business growth: rate of start-up growth, share of scale-ups, and high-growth company density. Data sources for the Kauffman Index calculations are based on Current Population Survey (CPS), with sample sizes of more than 900,000 observations, and the Business Dynamics Statistics (BDS), which covers approximately 5 million businesses. The Growth Entrepreneurship Index also includes Inc. 500/5000 data."