The number of completed reviews in the first nine months of 2018 was down year on year in all disciplines except media, AAR's latest New Business Pulse shows.
Overall, the number of reviews was down 8.2%. The decline was most severe in integrated accounts (down 27.4%), followed by CRM/direct (a drop of 22.2%).
But even digital reviews – which were showing growth in the first six months – were down 3.8% in January-September compared with the same period last year.
Media reviews, meanwhile, increased 12.8% and have included major brands such as Betway, the government (through the Crown Commercial Service), LV=, Specsavers, Sky and Whitbread.
Although advertising reviews saw a decline, AAR pointed to a positive move: the number of large accounts (£20m-plus) that switched agencies rose from five to nine, all of which went to the open market, when only one of the five did so (KFC) in 2017, with the others selecting form a roster or another walled garden approach.
The nine large accounts this year were Asda, Betfair, Betway, Camelot, Coral, Harveys/Bensons for Beds, SimplyBe, Moneysupermarket.com and Sky.
AAR identified four factors it said was keeping down the volume of reviews:
Brands looking for new ways of working, including in-housing and the creation of joint brand/agency teams
The introduction of GDPR causing clients to act more cautiously to ensure they are fully compliant, partly accounting for the large drop in CRM/direct reviews
Agencies becoming "stickier" as they expand their services, making clients less likely to seek change
Marketers putting more of their focus on technology, innovation, data and business infrastructure, making it harder for them to give attention to reviewing their agencies in traditional disciplines
Kerry Glazer, chief executive of AAR, said agencies had encountered a "very tough market" this year and there was no evidence that this would change any time soon.
"2018 has not been a year when new-business ambitions have been easily achieved," she said. "A big factor in this is certainly the fact that business issues outside of marcoms are taking a greater share of the CMO’s attention.
"We are already being asked about 2019 and, being candid, we see no reason why the new-business market will change significantly from its current state over the next two quarters.
"Putting the notion of an extension to Article 50 to one side, a ‘wait and see’ attitude is likely to prevail until 29 March 2019, when we are officially due to leave the EU. But, following this deadline, brands’ desire to get on with it may supersede concerns about an uncertain future."