5 Biggest Industries in the US Heading into 2023

3. Professional, scientific and technical services

Average gross domestic product of the industry in 2021 (in billions): 1,956.3

Gross domestic product of the industry in Q1 2022 (in billions): 1,978.6

The professional, scientific and technical services industry includes services provided to other clients in various industries including architectural, engineering, research services, advertising services and many more. The biggest occupation in this industry is accountant and auditors.