The "Stability Index" is a measure of how much the forecast deviates from the recent past. The assumption is that on aggregate the forward looking 13 week average should not deviate excessively from the previous 13 weeks. Even in seasonal products there should be a semblance of balance. As such, when we see a high importance item with a low stability index (under 50%) it is a strong signal that the item should be reviewed to assure something is not out of balance.
The "Stability Index" is calculated as: (1-((ABS((13WAForecast-13WAHistory))/13WAHistory))*100
The Index is found in three primary interfaces: