The findings show that agencies have been hardest hit by shrinking Government budgets during 2007-12, as overall marcoms budgets have dropped to around three-quarters of their spend five years ago. Just a handful of bodies are preparing to use agencies this year.
The figures reflect the swingeing cuts to comms introduced by the coalition Government in 2010-11, and the closure of the COI last year.
The Cabinet Office last week vowed to spend £285m on comms during the 2012-13 financial year - an apparent rise on the past two years' spend.
The number of comms staff within Government has fallen by 11 per cent from five years ago, and staff numbers are likely to fall a further seven per cent based on trends from PRWeek's figures.
The Department of Health could be worst affected with the expected loss of around 40 comms jobs.