All twelve sectors ranked over a day, a month or a year, aggregated cap-weighted — a sector's move is what its largest names did, not the average of its members. The rotation view adds the part that is actually useful: which sectors historically lead in each phase of the economic cycle, which is the same relationship the engine's own sector modifiers encode.

Technology leads in early expansion; utilities lead in recession. Knowing that is the difference between four percentages and a reason to move money.