One common way to address this is to add an empty sheet after Sheet1 and
before any of the sheets you want to sum. Name the new sheet FirstSht (for
example). Add another empty sheet after the last sheet you want to sum. Name
this new sheet LastSht. On Sheet1 use a SUM formula like

=SUM(FirstSht:LastSht!AD8)

FirstSht & LastSht don't affect the total because they are empty. If new
sheets are added anywhere between FirstSht & LastSht, they will automatically
be included in the SUM formula range.

Hope this helps,

Hutch

"musha-bsuha" wrote:

I'm trying to sum data in Sheet1 from 50+ other sheets in the same file,
using =SUM(EUN1!AD8+EUN2!AD8+SV!AD8....and so on. However, I need to ammend
the formula every time new sheet is added.

Is there a formula which will automatically count the values in the
respective cell in all sheets, irrespectively how many are added?

Thanks a million!