I'm sure this is a very silly question, but I don't know
how to phrase it to get answers from Help.

I have a sheet with several columns. Each column a different colour.
There's data in a number of rows.

As I scroll down the rows, there is no end. The empty coloured columns
continue as long as I scroll down.

Can I set an absolute end? Is this wasting memory or space? The
workbook does take ages to open.

I do have a finite rightmost column.

Any help appreciated.

Thanks - Kirk