Colors in Gantt chart PDF are not explained

Colors in Gantt chart PDF are not explained

Hello everyone 

I have noticed that when I generate a PDF report of the Gantt Chart it bears no reference to the colors used, such as "green" it would be "planned" appears not explained as such (so: green equals planned) 

This makes people not very familar with Gantt charts diagrams I constantly ask what meaning is the green color? yellow, blue? etc. 

Thank you!