“For each dollar of office building expenditures, the U.S. economy gains $2.57,” said Stephen Fuller, the George Mason University professor who authored the report. And for every one of those dollars, nearly 20 jobs not related to the building itself are supported.

The average cost to manage the 9.9 billion square feet managed by the organization’s members is $8 per foot. Fuller said that translated to an economic contribution to the GDP of $205 billion and 1.6 million jobs.

When all of the factors are calculated, office real estate contributed nearly one-third of the nation’s $15 trillion.

In other areas of commercial real estate, retail workers contribute $9,800 each to GDP, hotel workers $34,600 and industrial workers $139,000, Fuller said.