An ethical dilemma

OK so I have this ethical dilemma.  I have a massive stash which I know there is little chance of me stitching in my lifetime so I am planning on selling some of it.  However the majority of the patterns I want to sell I would also like to stitch at some point.

Now when I stitch a chart I make a working copy and then sell the original pattern afterwards.  So my question is would it be ethical or not to make a working copy of a pattern that I may (or very likely may not) stitch in the future and sell the chart now before I actually stitch it.  Obviously I couldn't do this with my HAED charts as these are all electronic, I am only talking about the patterns that I have actually purchased hard copies of.

I'd love your opinions on this either in the comments or in the poll.

Thanks

Nic