Quantity does not match data

[#1]

If you look at the attached dashboard, you will see the sum for the date 01/05/2011 is 28 in the chart.

Yet looking at the raw data, this value should only be one.

I know this is something to do with how I have linked my sales transaction to the master calender, as removing this link corrects the chart.

I just can't see why.

What I am hoping to do is to use some calculations similar to below, to compare periods of time

<Period = {"<=$(=Max(Period))"}, Year = {"$(=Max(Year))"}, Quarter = , Month = >

<Period = {"<=$(=Max(Period))"}, Year = {"$(=Max(Year)-1)"}, Quarter = , Month = >

I have to generate my Master Calender differently because the dates are linked to Accounting Periods.

Thanks

Andy