A "climber" is a release which is going higher in the chart week-on-week. Because chart positions are generally relative to each other on a week-to-week basis, a release does not necessarily have to increase sales week-to-week to be a climber, as if releases ahead of it decline in sales sufficiently they may slip below it. By the same metric, not all week-to-week sales increases result in a climber, if other releases improve by a sufficient amount to keep it from climbing. The term "highest climber" is used to denote the release making the biggest leap upwards in the chart that week. There is generally not an equivalent phrase for tracks going down the chart; the term "faller" is occasionally used, but not as widely as 'climber'.