This is regarding the keyword performance pop-up on the bottom left of the Home tab. For best (& worst) performing keywords, it shows keywords that have twice (or half) the average CTR for the time period. Is this the average CTR for the entire account? The campaign that each keyword is in? The ad group that each keyword is in? Also, under the competitive keywords dropdown, how does Google determine which keywords are 'competitive'? Is this a simple calculation or something using a complex algorithm as with quality score?