# Welcome to the Highcharts Gantt JS (gantt) Options Reference

These pages outline the chart configuration options, and the methods and properties of Highcharts objects.

Feel free to search this API through the search bar or the navigation tree in the sidebar.

# series.xrange.index

The index of the series in the chart, affecting the internal index in the `chart.series` array, the visible Z index as well as the order in the legend.