Interpublic Group's global organic revenue dropped 9.9% between April and June because of the impact of the coronavirus pandemic.
The company, which owns agencies including McCann, R/GA and MullenLowe, reported net revenue of $1.9 billion, down 12.8% year on year.
Operating profit plummeted 84.7% to $40.5 million compared with $264.2 million during the same period last year. Yesterday, rival Omnicom reported a similar fall of 89% in operating income.
In its second-quarter financial results, published today, IPG added that the Covid-19 outbreak has led it to reduce its workforce around the world by about 1%. IPG has approximately 54,000 staff.
It also plans to give up about 500,000 square feet of leased office space in 40 locations.
As a result IPG reported $112.6 million in restructuring charges for the first half of the year "with the objective of lowering our operating expenses structurally and permanently relative to revenue and accelerating the transformation of our business".
Michael Roth, chairman and chief executive of IPG, said: "As expected, our results bear the imprint of the severity of the health crisis and its economic impact. However, our companies and our people have adjusted quickly to these uncertain times and new ways of working, as evident in our results, which once again show IPG outperforming the sector.
"We remain new-business positive, year to date, and our pipeline of business opportunities is solid. We initiated a programme of structural operating cost reduction to lower our expense base, and raise our margin opportunities going forward. Our balance sheet and liquidity continue to be further areas of strength."
IPG fared slightly better than Publicis Groupe, which reported a 13% fall in global organic revenue last week. WPP's results are expected on 27 August.