Unable to resolve #DIV/0!

[oomfh]

Using:

=(SUM(+'7Jan%'!$AL8,'14Jan%'!$AL8,'21Jan%'!$AL8,'28Jan%'!$AL8,'4Feb%'!$AL8,'11Feb%'!$AL8,'18Feb%'!$AL8,'25Feb%'!$AL8,'4Mar%'!$AL8,'11Mar%'!$AL8,'18Mar%'!$AL8,'25Mar%'!$AL8,'1Apr%'!$AL8))/(SUM('7Jan%'!$AM8,'14Jan%'!$AM8,'21Jan%'!$AM8,'28Jan%'!$AM8,'4Feb%'!$AM8,'11Feb%'!$AM8,'18Feb%'!$AM8,'25Feb%'!$AM8,'4Mar%'!$AM8,'11Mar%'!$AM8,'18Mar%'!$AM8,'25Mar%'!$AM8,'1Apr%'!$AM8))

 

[Jonmo1]

I'm assuming these sheets are all in order left to right, 7Jan to 1Apr

Try
=IF(SUM('7Jan%:1Apr%'!AM8)=0,"",SUM('7Jan%:1Apr%'!AL8)/SUM('7Jan%:1Apr%'!AM8))

 

[lownote14]

I'm no expert on the matter but the parenthesis that you have containing each sum statement, might be un-needed.

So instead of:

=(SUM(+'7Jan%'!$AL8,'14Jan%'!$AL8,'21Jan%'!$AL8,'28Jan%'!$AL8,'4Feb%'!$AL8,'11Feb%'!$AL8,'18Feb%'!$AL8,'25Feb%'!$AL8,'4M ar%'!$AL8,'11Mar%'!$AL8,'18Mar%'!$AL8,'25Mar%'!$AL8,'1Apr%'!$AL8))/(SUM('7Jan%'!$AM8,'14Jan%'!$AM8,'21Jan%'!$AM8,'28Jan%'!$AM8,'4Feb%'!$AM8,'11Feb%'!$AM8,'18Feb%'!$AM8,'25Feb%'!$AM8,'4Mar %'!$AM8,'11Mar%'!$AM8,'18Mar%'!$AM8,'25Mar%'!$AM8,'1Apr%'!$AM8))

You would have:

=SUM(+'7Jan%'!$AL8,'14Jan%'!$AL8,'21Jan%'!$AL8,'28Jan%'!$AL8,'4Feb%'!$AL8,'11Feb%'!$AL8,'18Feb%'!$AL8,'25Feb%'!$AL8,'4M ar%'!$AL8,'11Mar%'!$AL8,'18Mar%'!$AL8,'25Mar%'!$AL8,'1Apr%'!$AL8)/(SUM('7Jan%'!$AM8,'14Jan%'!$AM8,'21Jan%'!$AM8,'28Jan%'!$AM8,'4Feb%'!$AM8,'11Feb%'!$AM8,'18Feb%'!$AM8,'25Feb%'!$AM8,'4Mar %'!$AM8,'11Mar%'!$AM8,'18Mar%'!$AM8,'25Mar%'!$AM8,'1Apr%'!$AM8)

That might help, if what you are doing is incredibly specific to this formula you have, otherwise I would try what jonmo1 posted.
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