Two towns report that household water use has fallen. In one, consumption drops from a high level after a drought campaign. In the other, use declines only slightly from an already low level maintained for years. Ranking the towns solely by the percentage decrease rewards the first for a large improvement but may overlook the second's continuing efficiency. Ranking them solely by current consumption tells a different story and may conceal the first town's recent progress. Neither comparison is necessarily wrong. They answer different questions: how much a place has changed, and how efficiently it now operates. A fair interpretation states the starting point, the direction of change, and the present level. Without that separation, a measure intended to recognize improvement can be mistaken for a complete judgment of performance.