For anyone else looking at a similar solution but for multiple reports, please note that while @ramesh_neel's solution works very well in this situation (and should be marked as the solution), it will not work if you're trying to generate multiple reports grouped by a certain category such as product type etc. as it will group them all into the one since you're grouping on date only. The solution to this is to create a new field and append the category + datetimenow() function then group on that in your report generation. See my attached workflow for an example.
