Trying to do this power query!

Anonymous , You have

https://docs.microsoft.com/en-us/powerquery-m/table-min

https://docs.microsoft.com/en-us/powerquery-m/table-max

and

https://docs.microsoft.com/en-us/powerquery-m/list-max

https://docs.microsoft.com/en-us/powerquery-m/list-min

seeif these can help

Change the #"Changed Type" reference to the previous step in your query and try this:

([Performance] - 
List.Max(Table.Column( #"Changed Type" , "Performance" )))
/ 
(List.Max(Table.Column( #"Changed Type" , "Performance" )) - 
List.Min(Table.Column( #"Changed Type" , "Performance" )))

/ J