Locale-aware number format for the tick values in the second X axis. Overrides numberFormat for this axis; an explicit xAxis2TickFormat takes precedence over it. It could be a preset name (comma, percent, dollar, euro, pound, yen, compact), a sprintf format string, or an object, i.e. {"locale": "en-US", "style": "decimal|percent|currency|compact", "currency": "USD", "decimals": 1, "grouping": true, "prefix": "", "suffix": ""}
string or object
Area,
AreaLine,
Bar,
BarLine,
Boxplot,
Bubble,
Bullet,
Chord,
Circular,
Contour,
Correlation,
Density,
DotLine,
Dotplot,
Dumbbell,
Fish,
Gantt,
Heatmap,
Histogram,
Line,
Lollipop,
Map,
Meter,
OptionsWall,
ParallelCoordinates,
Pie,
Radar,
SPLOM,
Sankey,
Scatter2D,
Scatter3D,
ScatterBubble2D,
Stacked,
StackedLine,
StackedPercent,
StackedPercentLine,
Streamgraph,
Sunburst,
TagCloud,
Tree,
Treemap,
Violin,
Waterfall