Prices for television advertising will fall to their lowest level since 1987 as the downturn continues to hit marketing budgets, according to forecasts from Zenith Optimedia, a media agency.

Zenith said that in real terms, slots for UK TV cost 40 per cent less than in 1987, when it began collecting pricing data. The agency, which is part of Publicis Groupe, forecasts television advertising revenues to fall by 3 per cent next year, returning to modest growth of 2 per cent in 2010 and 1 per cent in 2011.