Marketers and analysts not only want to know which channels & campaigns drive sales and what is their ROI. They want to know how to optimize digital marketing performance starting from strategy and up to keywords bids adjustment. As advertising tools evolve, campaign optimization inside a particular ad service is being constantly improved. The main decision for a marketing professional to make is how to choose the perfect budget allocation across the channels and how to know in advance what results one can expect from each channel in the future.