# A request regarding an over function statement

Hi Spotfire experts:

One customer of ours runs into an issue using the OVER function in a cross table.

We put the date column in the column axis and the value formula in each cell looks like this:

**( Sum([txn_amt]) - (Sum([txn_amt]) OVER (LastPeriods(3,[Axis.Columns])) / 3) )
/
(Sum([txn_amt]) OVER (LastPeriods(3,[Axis.Columns])) / 3)**

Bascially what's showing here:

Sum([txn_amt] is the **Current Month Value**

(Sum([txn_amt]) OVER (LastPeriods(3,[Axis.Columns])) / 3) is the **Average Value for Last 3 Months**

We are trying to compute the **Variance % **between those two.

But this expression won't work in the cross table.

Could someone give us some guidance?

Thanks in advance!

Chen

+ Add a Comment