(AP) -- Google has pulled back another curtain and revealed the size of its lucrative Internet ad network in the U.S. It spans more than 1.5 million advertisers and websites.
The Associated Press calculated the figure from a state-by-state breakdown of Google Inc.'s operations the company released Tuesday.
It marks the second time in two days that Google has shared previously unknown details about the marketing channel that generates most of its revenue. The Internet search leader spelled out the commissions that it pays its ad partners Monday.
Tuesday's breakdown came as part of Google's attempt to quantify its economic impact in the U.S.
The snapshot also revealed that Google has at least 12,200 workers in the U.S., primarily in California, New York and Washington state. The company employs 20,600 people worldwide.
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