(ShareCast News) - Advertising agency WPP put out a brief update on its February performance in response to demand from a number of investors and analysts.The company, which reported its full year results last Friday, said like-for-like revenue and net sales growth were both "well over 3%" last month.Shares in the company fell at the end of last week as it posted solid like-for-like net sales growth of 3.3% for 2015, but sounded a cautious note on the outlook.Chief executive Martin Sorrell said: "The always on, Don Draperish, general industry optimism seems misplaced."