Worldwide revenues, hampered by less-favourable currency exchange rates, increased 2.1% to $3.56bn (£2.28bn), although organic growth topped that at 5.1%.
In dollar terms, Eurozone revenues dropped 12.9% to $576.6m (£369.1m), but the US, the UK and the other region Omnicom classes as "rest of the world" grew.
The UK, where Omnicom strengthened its DDB network with the estimated £60m acquisition of Adam & Eve in May, reported revenue growth of 2.3% to $310.9m (£!99m)and organic growth of 3.2%.
The owner of creative networks BBDO and TBWA and media networks OMD and PHD has grown revenue and net income in every quarter since the spring of 2010.
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