To me this boils down to Churchhills adage "Don't trust a statistical report unless you fabricated it by yourself". There are so many subtleties when translating business questions into SQL e.g. was the average deal size in the post's "trend" example computed using average/median/geometric mean formula? Should the trend only contain historic or also projected values. No serious report comes without data definitions, then its an exercise to the reader to spot flaws there.