Professional employer organizations generate between $136 billion and $152 billion in gross revenues; provide services to between 2.7 million and 3.4 million workers; and offer HR, benefits and compliance assistance to between 156,000 and 180,000 small to mid-size businesses, according to a new study released by the National Association of Professional Employer Organizations at its annual conference in Phoenix.

The new study also found the PEO industry added, on average, roughly 100,000 worksite employees and 6,000 net new clients in each of the last 30 years.

“This study proves through hard data that the PEO industry is a vibrant, impactful and growing sector of the US economy,” said NAPEO President Pat Cleary. “PEOs provide clear competitive advantages to their small and mid-size business clients, and more and more businesses are embracing the PEO concept and capitalizing on the benefits of using a PEO.”

The number of US PEOs range from 780 to 980, according to the report. States with the most PEOs and their estimated number of PEOs include:

• Florida: 107
• Texas: 100
• California: 59 to 77
• New York: 47
• Michigan: 45 to 59

“As this study highlights, the PEO industry is larger than the agricultural industry in the US, and comparable in size to the federal government and the education sector,” said Cleary. “Combined with last year’s passage of the Small Business Efficiency Act creating IRS recognition of the industry, it’s evident that PEOs are poised for even greater growth and impact.”

Economists Laurie Bassi and Dan McMurrer of McBassi and Associates conducted the study. Data sources used focused on NAPEO membership data; US Bureau of Labor Statistics data; NAPEO’s 2014 Financial Ratio & Operating Statistics Survey; Hoovers/Dun & Bradstreet data on all companies classified as PEOs by Hoovers; and detailed administrative data from five selected states.