Impact combines two scores: reach (how many people in the UK it touches) and depth (how much it matters to them). The min-impact control (top right) hides everything below that score, so you can flip between the full firehose and only the big stuff. Balanced = √(reach × depth), which stops broad-but-shallow moments outranking things people deeply care about; average = simple mean. ~ marks dates that are provisional or typically confirmed nearer the time.