Description: ast three values of the data range to create the sub-chart, in contrast to Microsoft 365's default, which groups the last two values. This discrepancy not only limits customization options but also introduces potential confusion for users who expect behavior consistent with other productivity suites. Currently, the user interface lacks the functionality to modify how many values are grouped or which ones are included, leading to a lack of control and flexibility in chart customization. Enhancements in this regard are necessary to improve user experience and provide greater control over chart presentation. Actual Results: The last three values of the data range are grouped to construct the sub-chart. Expected Results: The user should have the option to customize the grouping behavior, including the ability to specify the number of values to be grouped or to choose which ones are included in the sub-chart. Reproducible: Always User Profile Reset: Yes Additional Info: LibreOffice version: 24.8.0.0.alpha1+ (X86_64) / LibreOffice Community Build ID: 658a212585c56540a17c41111e6829716d4ef4e3 CPU threads: 8; OS: Linux 6.5; UI render: default; VCL: gtk3 Locale: en-AU (en_AU.UTF-8); UI: en-US Calc: CL threaded