Researchers often look at ad spend predictions as a rough guide to how their industry might fare. In which case, the latest revised forecasts from WPP’s GroupM, Interpublic’s Magna Global and Publicis’ ZenithOptimedia don’t bring much cheer.

Each predicts that global ad spending will grow by various amounts next year but the growth figures themselves have been scaled back.

For GroupM, spend will now be up 6.4% to $522bn, down from the 6.8% forecast in July.

Magna Global, meanwhile, expects growth of 5%, revised down from 6.5%, to $449bn.

And finally, ZenithOptimedia predicts ad spend will rise by 4.7% to $486bn, down from the 5.3% rate anticipated in October.