Grouping cells together break sorting

Hello,

I'm working on this spreadsheet right now which lists my music CDs collection;
For each album, notice I've grouped cells together to list all the songs of the album - The rating (column O) of the album "The Three Words to Remember in Dealing with the End" is 95%, which is calculated with the average of every song of the album. This works:
=AVERAGE(O18:O21)



The only concern with grouping cells together, is when I want to sort the albums rating, from smallest ratings to highest. Obviously trying to sort them makes the result incorrect. The album "The Three Words to Remember in Dealing with the End" should be the highest rated at 95%.



Obviously the songs listed under "The Three Words to Remember in Dealing with the End" are also incorrect - these songs are from a totally different album.

I understand that the formula =AVERAGE(O18:O21) is intended for specific cells, and so when you sort the Rating column, these cells changes, so it break normal sorting. I wonder how I should reorganize/restart my document to acheive what I would want to do. Any advice?

Thank you, I appreciate it.

Fixed;
I just put the songs in a new sheet of his own. That way when I've sorted the albums by ratings, it still work.
Was actually simple.