I've also noticed that creating charts based on different date groupings, e.g. by day, week and month do not match, i.e. total of all days in march, does not match the value for march in the 'group by month' version of the same chart.
I currently have my date mysql data in a "date + time" format; could this be the problem?
Sorting by date seems to make no difference, and when I re-enter the wizard this sorting info is lost (i have DWC version 1.04).
Any assistance you can provide would be gratefully received as i really need to get this sorted.