By Elliot Gulliver-Needham Like-for-like revenue at advertising giant WPP ticked up 4.1 per cent in the quarter to 30 September, despite a decline in business outside of the US and Europe. However, net new billings declined year-to-date. The figure came in at $3.2bn (£2.5bn) compared to $3.4bn (£2.6bn) in 2023. However, other regions struggled. Revenue in the UK was flat, while Chinese revenue declined 21.3 per cent, and the rest of the world dropped by 2.2 per cent. WPP’s subsidiary Groupm was another bright spot. Revenue jumped 4.8 per cent throughout the quarter. Like-for-like revenue less …