[Power Query] Calculate Average For columns of the same Year

[Anonymous]

Hello, everyone!

I have the following table structure.

Site Name	Account Number	12/1/2018	11/1/2018	10/1/2018	9/1/2018	8/1/2018	7/1/2018	6/1/2018	5/1/2018	4/1/2018	3/1/2018	2/1/2018	1/1/2018	12/1/2017	11/1/2017	10/1/2017	9/1/2017	8/1/2017
Name	12	50	50					50	50
Name 2	123	3919	3919	3332		50	50		3919	3332						50	50
Name 3	123					3919	3919	3332								3919	3919	3332

What I wanto to do is create a new column with the average for the values that are in columns with same Year (Red values on table above that belong to the same line, for example). 

I´ve tried this.

         1 - Create a function that returns the columns with , for example, 2018 as year

(Table)=>

let
    Custom1 = Record.ToTable(Table{0}),
    #"Removed Columns" = Table.RemoveColumns(Custom1,{"Value"}),
    #"Removed Top Rows" = Table.Skip(#"Removed Columns",2),
    #"Added Custom" = Table.AddColumn(#"Removed Top Rows", "Ano", each Text.End([Name],4)),
    #"Filtered Rows" = Table.SelectRows(#"Added Custom", each ([Ano] = "2018")),
    #"Removed Columns2" = Table.RemoveColumns(#"Filtered Rows",{"Ano"}),
    Custom2 = Table.ToList(#"Removed Columns2")
in
    Custom2

           2 - Tried to create the new column using the list names above as reference.

= Table.AddColumn(Table, "Average", each List.Average(ListarAno2018(Table)), Currency.Type)

I think that I´m close to get it, but the code on step 2 doesn´t accept the list as reference.

Thank you all so much for any help!

[v-piga-msft]

Hi @Anonymous,

I have a little confused about your requirement.

If it is convenient, could you share your desired output based on your sample data so that we can understand your scenario better.

Best Regards,

Cherry

[Anonymous]

Hello, @v-piga-msft!

Here´s the output that I´m looking for..(Image below)

One more thing, the new query must calculate the average regardless the number of columns with a specific year date. Therefore, it must calculate even if the number of columns with "2018" or "2017" be different of 2 as the example illustrates.

Thank you!