help with cumulative expression for chart

[#1]

Hi all,

I am trying to create a cumulative chart like the one below:

note: the top chart uses the "full accumulation" option and the bottom chart is the absolute values which is simply sum(CallsAnswered).

Using full accumulation is fine in this example because the expression is just a simple sum. But for other expressions it won't work eg. service level which is sum(CallsAnsweredB4Threshold)/sum(CallsAnswered). So I need to use an alternative.

I tried aggr(sum(CallsAnswered), Hour) but this produces exactly the same as the absolute graph and doesn't accumulate.

Can someone offer a solution?

Many thanks.

[#2]

Does anyone have an idea on this?

[#3]

C'mon, someone must have an idea on this............

This is an example of call centre service level. I thought of something like this:

sum

(CallsAnsweredB4Threshold) as expression1 with full accumulation

sum(CallsAnswered) as expression2 with full accumulation

Then, I would disable both of these expressions in the chart and create a third expression which is expression1 / expression2 (thinking along the lines of column1 / column2 in a table). And voila, I would have a cumulative line for service level. Only problem is, I can't seem to make it work.

Can anyone help?

[#4]

Does anyone have an idea on this? Perhaps using ABOVE or RANGESUM or a combination of both + something else?

Can someone please help with this?