You'd have to use the offset() function

=offset('Activity Sheet'!$C8,(column(A1)-1)*65,0)

Use that in place of

=+'Activity Sheet'!$C8

& copy it over

"Dave" wrote:

As I drag the formulas below across multiple coulmns on the "Time Sheet" tab,
is there a way to have the row reference for each update by 65? The data on
the Activity Sheet tab is arranged down the tab while the summary on the
"Time Sheet tab goes across the tab.

Thanks
David

=+'Activity Sheet'!$C8 -- =+'Activity Sheet'!$C73 -- =+'Activity
Sheet'!$C138
=+'Activity Sheet'!$C13
=+'Activity Sheet'!$C18
=+'Activity Sheet'!$C23
=+'Activity Sheet'!$C28
=+'Activity Sheet'!$C33
=+'Activity Sheet'!$C38
=+'Activity Sheet'!$C43
=+'Activity Sheet'!$C48
=+'Activity Sheet'!$C52
=+'Activity Sheet'!$C56
=+'Activity Sheet'!$C64