Why can the value of a percentage metric exceed 100% when fold is applied?

When fold is applied to a percentage metric, the value can exceed 100% because aggregation transformations can modify how metrics are interpreted and represented. Specifically, when aggregation occurs, the context of units and their meaning can change. This means that the new calculated metric may not adhere strictly to the original unit semantics, allowing for values that conceptually extend beyond the traditional limits, such as a percentage exceeding 100%.

For instance, if the aggregate function sums values from various data sources that individually might each reflect percentages relative to different denominators or totals, the resultant metric can portray an aggregation that goes beyond the expected range. Therefore, the aggregation transformations enable this possibility, allowing the final result to exceed the conventional boundaries of a percentage metric.