YouGov may have been the most successful pollster when it worked for CBS and The Economist in last year's American presidential election but that wasn't enough to stop its profits from tanking.

First-half headline pretax profits fell from £5.2 million to £2.4 million in the six months to the end of January.

Revenues rose 20% to £22.6 million but much of that was owing to the strength of the dollar with underlying growth nearer 4%.

Chief executive Nadhim Zahawi said: "Things were going very well in the first quarter. Then suddenly in December the world gasped and held its breath through January and February.

"It was the difference between people reading about the recession in their newspapers and actually seeing their friends and colleagues lose their jobs."

Zahawi said that while political polling grabs the headlines, it is only 2.5% of revenues.

The bulk of YouGov's work is hard-edged commercial polling - helping companies to find out what consumers need or are still prepared to buy in a recession.

The firm has even launched services in tune with the times, including Recession Tracker, Debt Tracker and Dongle Tracker.

"We tooled for further growth which was suddenly whipped away," Zahawi admitted. The panel of people who regularly fill in its online polls has grown from 1.4 million to 2.2 million. But 30 out of YouGov's 420 staff around the world are to lose their jobs over the coming months.

That should save £300,000 this year and more like £2.5 million in a full year.

Zahawi said trading since February had not improved and said the outlook remained "very uncertain". But YouGov has almost £14 million in the bank and Zahawi remains convinced that online polling is still set to be one of the fastest growing areas of the media.

The shares which have fallen by three quarters in the past 12 months rose 3½p to 39½p.