# Introduction
The xViz Gantt Chart provides you with the option to display **Reference Lines** (based on dates) and **Reference Ranges** on the chart thereby giving an indication of where you are in the project and to assess the level of completeness.
**Reference Line** - A date line spanning across all the tasks. Configuration of one date will add the reference line on the Chart.
**Reference Band** - Range of continuous dates highlighted in the tasks. Configuring two dates ranges will be highlighted as a band in the chart.
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We can display the Reference line and Reference Range with Static Approach using the Reference tab which is located in Advance Editor - [Static Approach](/project-management/reference-lines-and-reference-range/static-approach.md)
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