The research also reveals the IT sector suffered the biggest drop, with year on year permanent vacancies falling by more than 12%.
Monthly trends reports by APSCo, a UK professional recruitment industry body, provide a regular update on the professional staffing market. This includes sectors such as banking and finance, healthcare, engineering and sales.
The research also shows that the number of professionals being placed in temporary assignments is still rising, with a jump of 4.5% year on year. The most notable increases are evident in marketing and media (9%) and IT (6.5%).
The report states that while the number of people being placed in permanent roles has fallen significantly, temporary vacancies are still rising, suggesting a marked skills shortage which is being plugged by the use of temporary staff.
Ann Swain, chief executive of APSCo, said: "Employers still haven't got the confidence to invest in permanent hires against this backdrop of ongoing uncertainty."
John Nurthern from Staffing Industry Analysts, which compiles the data on behalf of APSCo, said: "In light of the weaker economic figures that came through at the end of last year, it is not at all surprising to see that demand for professional hires is soft.
"We do not believe that we'll see much improvement until the summer at the earliest, but the UK economy, and those of its main trading partners, remains fragile and a pick-up in the latter half of the year is by no means guaranteed."