sum with counta & countif with many matching criteria

Hello,

I have a problem with placing a formula in b24 so I can copy it accross and down.

I have tried to do combination of sums and counta's and countif's (only to minus N/A) in the range of index / match.

What I want to achive is:

in Actual section - I need to sum all percentages within the week required (in the Actual column in the top table) and then devide it by the number of cells that does not contain N/A.

in 5 days section - I need to sum all percentages within the range of Monday to Friday (in the top table) and devide it by 5

in 7 days section - I need to sum all percentages within the week Monday to Sunday (in the top table) and devide it by 7.

I do not know if I was using the right combination and if I actually used the right functions.

If anybody has any idea on how I can resolve this problem it would be great to share that knowledge.

Thank you Guys

Simon