[ms-xlsx]: Excel (. xlsx) Extensions to the Office Open xml spreadsheetml file Format

extLst: A CT_ExtensionList ([ISO/IEC29500-4:2011] section A.2) element that specifies future extensibility for this element.

Attributes:

pivotCacheId: An unsignedInt ([XMLSCHEMA2] section 3.3.22) attribute that specifies the associated non-OLAP PivotTable ([ISO/IEC29500-1:2011] section 18.10) PivotCache. MUST match the pivotCacheId attribute of an existing CT_PivotCacheDefinition element.

sortOrder: An ST_TabularSlicerCacheSortOrder attribute that specifies how the non-OLAP slicer items are sorted in the slicer view.

customListSort: A Boolean ([XMLSCHEMA2] section 3.2.2) attribute that specifies whether custom lists are used when sorting the non-OLAP slicer items.

Value	Meaning
"false"	Custom lists are not used when sorting the non-OLAP slicer items.
"true"	Custom lists are used when sorting the non-OLAP slicer items.