XYZ segmentation is the classification of planning objects based on their demand volatility, which can be established using two different calculation strategies: Calculate Variation and Aggregate over Periods.
The main difference between the two strategies is that Calculate Variation calculates the variance values during the segmentation runs, while Aggregate over Periods works with values that were previously calculated by other tools such as the Manage Forecast Error Calculations app.
Calculate Variation:
If you choose this calculation strategy, the system evaluates the fluctuations in the historical demand or consumption during each segmentation run and classifies planning objects based on their regularity or propensity for planning.
The following calculation methods are available for this purpose:
Coefficient of Variation (CV):
If you choose this method, the system assigns each item to various segments based on their coefficient of variation, which is the standard deviation divided by the mathematical mean value for a specific time frame:

In the formula above, σ is the standard deviation and X̅ is the mathematical mean.
Coefficient of Variation Squared (CV Squared):
If you choose this method, the system divides the square of the deviation with the square of the mean, getting CV squared as a result. CV squared is considered more convenient than CV for evaluating demand fluctuation.
Consider the Results of Time Series Analysis:
When forecast automation is run in the Application Jobs app, the system analyzes the time series values stored in the selected input key figure and saves the identified properties in the background. If you select Consider Results of Time Series Analysis for XYZ segmentation, the system will automatically use the analysis results to remove any trend or seasonality from the time series data if necessary and calculate CV or CV Squared based on this transformed time series. Both trend and seasonality are known to distort the segmentation results because they indicate volatility despite often being predictable.
Let’s say, for example, that the CV calculated for a planning object is 0.6 with an observed trend left untouched, which means that the item would be assigned to segment Y. With the trend removed, the CV calculated for it is 0.2, which means that the item would be assigned to segment X. Since the second CV value is lower than the first one, the system automatically chooses X as the segmentation result.
If the time series data is intermittent, it may happen that the CV value is higher after the cleansing than before. In this case the planning object gets assigned to the segment that was calculated based on the original segmentation measure values.
Note: The analysis results can only be considered if time series analysis has already been executed for the input key figure of XYZ segmentation.
Aggregate over Periods:
If you choose this calculation strategy, the system performs the following steps:
It retrieves the segmentation measure values that were calculated by another tool such as the Manage Forecast Error Calculations app.
It processes the segmentation measure values using the aggregation method that you select.
It compares the results of the calculations to the thresholds you specified and assigns the planning objects to XYZ segments accordingly.
This calculation strategy is useful, for example, if you want to classify the planning objects based on a forecast error measure such as MAPE.
The following aggregation methods are available:
Minimum: The smallest value produced by an item is compared to the thresholds.
Maximum: The largest value produced by an item is compared to the thresholds.
Average: The average of all values produced by an item is calculated and compared to the thresholds.
Sum: The values produced by an item are summed up and the total value is compared to the thresholds.
Note
This calculation method is identical to segmentation method no. 5 in ABC segmentation.