OptionalalwaysOptionalcustomcustom function for returning tooltip HTML passed an array or object with the data, the default tooltip markup and the corresponding datum of the hovered element
Optionalcustomcustom function for calculating the total value receives all the data corresponding to the tooltip
Optionalenabledenable or disable tooltip
Optionalgroupcustomizes the Group label shown inside tooltips
Optionalshowshow total of items
Optionaltotalcustomizes the Total label shown inside tooltips
OptionaltruncationOptionalvaluea function to format the tooltip values
when true, always shows ruler tooltip instead of individual point tooltips