Help Using Offset to Count Values in Sections

[larissao]

Hello, I am trying to write a formula so that I can drag it down across many cells.
Basically, I want A:1 to count values in B1:B10, A:2 to count values in B11:B12, and so on.
I would like to be able to autofill column A rather than have to manually change the formula for each cell. Currently, when I drag the formula down, after counting B1:B10, it starts counting B2:B11.

Thank you for any help you can offer!

[puffinator]

The formula in A1 would be:

=SUM(OFFSET($A$1,(ROW()*10)-10,1,10,1))

Then copy down.

Change SUM to COUNT if that's the function you want, or COUNTA. You get the idea.

[TMS]

Another way, purely because I don't like OFFSET:

=LET(b,B:B,  base,(ROW()-1)*10,  SUM(INDEX(b,base+1):INDEX(b,base+10)))

[TMS]

To give you more flexibility:

=LET(b,B:B,  incr,10,  base,(ROW()-1)*incr,  SUM(INDEX(b,base+1):INDEX(b,base+incr)))

Change the incr variable if you want more or less rows.