Google "gantt chart filemaker 11"
Link #1 http://coresolutions.ca/how-to-gantt-charts-filemaker
Nov 23, 2010
How to: Gantt Charts in FileMaker
Link #8 http://www.briandunning.com/chartmaker/
ChartMaker Pro 7
for FileMaker Pro 5-11*
ChartMaker Pro is a collection of clever techniques using FileMaker's built-in features, not a plug-in. You may reuse these techniques in your own solutions without restriction, and can distribute your files to all other FileMaker users without the need to site license a plug-in.
xmCHART is a powerful FileMaker™ Pro plug-in for creating graphs of numerical data in which all important types of charts such as bar, scatter, line, area, bubble, high-Low, candlestick, pie, radar, polar and Gantt charts are supported.
Short answer: Repeating fields and conditional formatting!