Best practices to hide unwanted cells / columns

Hello,

I have a chart which require additional calculation to display bars properly. Those calculations are made in cells that I would like to be not visible.
But...

• Cells must be a part of table that chart can dynamically expand,
• They can't be hidden with option "hide column" because then chart won't show data. On the other hand, if I hide columns, and will turn on option to plot chart from hided rows / columns (sorry, but I do not have english version of Excel, so I don't know real name of this option), then autofilter doesn't work correctly. In that case there is no matter if I use filter on table or not, chart always display all data - which I do not want.

I thought about formating that cell into white font, so they cant be visible, but I want to ask if there is better (more elegant) way to do this.

Best Regards
Daniel